Bug 1776879, replace text/unicode for clipboard and drag and drop and use text/plain directly, r=edgar,mak,stransky,geckoview-reviewers,extension-reviewers,zombie,m_kato

Most usage is a straight replacement but gtk needs extra changes as it transfers plain text in UTF8 natively and needs to be converted into UTF16, and Windows uses single-byte characters for RTF and CF_HTML formats so we preserve this.

Differential Revision: https://phabricator.services.mozilla.com/D158587

accessible/tests/mochitest/common.js

@@ -847,11 +847,11 @@ function getTextFromClipboard() {
     return "";
   }
 
-  trans.addDataFlavor("text/unicode");
+  trans.addDataFlavor("text/plain");
   Services.clipboard.getData(trans, Services.clipboard.kGlobalClipboard);
 
   var str = {};
-  trans.getTransferData("text/unicode", str);
+  trans.getTransferData("text/plain", str);
 
   if (str) {
     str = str.value.QueryInterface(Ci.nsISupportsString);

browser/base/content/browser-places.js

@@ -1379,7 +1379,7 @@ var PlacesToolbarHelper = {
     }
 
     addData(PlacesUtils.TYPE_X_MOZ_URL, 0);
-    addData(PlacesUtils.TYPE_UNICODE, 0);
+    addData(PlacesUtils.TYPE_PLAINTEXT, 0);
     addData(PlacesUtils.TYPE_HTML, 0);
   },
 };

browser/base/content/browser.js

@@ -3176,7 +3176,7 @@ function readFromClipboard() {
     );
     trans.init(getLoadContext());
 
-    trans.addDataFlavor("text/unicode");
+    trans.addDataFlavor("text/plain");
 
     // If available, use selection clipboard, otherwise global one
     let clipboard = Services.clipboard;
@@ -3187,7 +3187,7 @@ function readFromClipboard() {
     }
 
     var data = {};
-    trans.getTransferData("text/unicode", data);
+    trans.getTransferData("text/plain", data);
 
     if (data) {
       data = data.value.QueryInterface(Ci.nsISupportsString);

browser/base/content/test/contextMenu/browser_contextmenu_contenteditable.js

@@ -93,9 +93,9 @@ add_task(async function test_contenteditable() {
     "text/html",
     PlacesUtils.toISupportsString("<strong>Bold text</strong>")
   );
-  xferable.addDataFlavor("text/unicode");
+  xferable.addDataFlavor("text/plain");
   xferable.setTransferData(
-    "text/unicode",
+    "text/plain",
     PlacesUtils.toISupportsString("Bold text")
   );
   Services.clipboard.setData(

browser/base/content/test/general/browser_bug1297539.js

@@ -29,7 +29,7 @@ function getTransferableFromClipboard(asHTML) {
   if (asHTML) {
     trans.addDataFlavor("text/html");
   } else {
-    trans.addDataFlavor("text/unicode");
+    trans.addDataFlavor("text/plain");
   }
   Services.clipboard.getData(trans, Ci.nsIClipboard.kGlobalClipboard);
   return trans;

browser/base/content/test/general/browser_clipboard_pastefile.js

@@ -16,12 +16,12 @@ function setClipboard(path) {
   trans.addDataFlavor("application/x-moz-file");
   trans.setTransferData("application/x-moz-file", file);
 
-  trans.addDataFlavor("text/unicode");
+  trans.addDataFlavor("text/plain");
   const str = Cc["@mozilla.org/supports-string;1"].createInstance(
     Ci.nsISupportsString
   );
   str.data = "Alternate";
-  trans.setTransferData("text/unicode", str);
+  trans.setTransferData("text/plain", str);
 
   // Write to clipboard.
   Services.clipboard.setData(trans, null, Ci.nsIClipboard.kGlobalClipboard);

browser/components/downloads/content/allDownloadsView.js

@@ -639,7 +639,7 @@ DownloadsPlacesView.prototype = {
     );
     trans.init(null);
 
-    let flavors = ["text/x-moz-url", "text/unicode"];
+    let flavors = ["text/x-moz-url", "text/plain"];
     flavors.forEach(trans.addDataFlavor);
 
     Services.clipboard.getData(trans, Services.clipboard.kGlobalClipboard);

browser/components/downloads/content/downloads.js

@@ -471,7 +471,7 @@ var DownloadsPanel = {
       Ci.nsITransferable
     );
     trans.init(null);
-    let flavors = ["text/x-moz-url", "text/unicode"];
+    let flavors = ["text/x-moz-url", "text/plain"];
     flavors.forEach(trans.addDataFlavor);
     Services.clipboard.getData(trans, Services.clipboard.kGlobalClipboard);
     // Getting the data or creating the nsIURI might fail

browser/components/places/PlacesUIUtils.sys.mjs

@@ -1793,7 +1793,7 @@ export var PlacesUIUtils = {
           let contents = [
             { type: lazy.PlacesUtils.TYPE_X_MOZ_URL, entries: [] },
             { type: lazy.PlacesUtils.TYPE_HTML, entries: [] },
-            { type: lazy.PlacesUtils.TYPE_UNICODE, entries: [] },
+            { type: lazy.PlacesUtils.TYPE_PLAINTEXT, entries: [] },
           ];
 
           contents.forEach(function(content) {
@@ -2034,7 +2034,7 @@ XPCOMUtils.defineLazyGetter(PlacesUIUtils, "URI_FLAVORS", () => {
   return [
     lazy.PlacesUtils.TYPE_X_MOZ_URL,
     TAB_DROP_TYPE,
-    lazy.PlacesUtils.TYPE_UNICODE,
+    lazy.PlacesUtils.TYPE_PLAINTEXT,
   ];
 });
 XPCOMUtils.defineLazyGetter(PlacesUIUtils, "SUPPORTED_FLAVORS", () => {
@@ -2271,7 +2271,7 @@ function getTransactionsForCopy(items, insertionIndex, insertionParentGuid) {
       });
     } else {
       let title =
-        item.type != lazy.PlacesUtils.TYPE_UNICODE ? item.title : item.uri;
+        item.type != lazy.PlacesUtils.TYPE_PLAINTEXT ? item.title : item.uri;
       transaction = lazy.PlacesTransactions.NewBookmark({
         index,
         parentGuid: insertionParentGuid,

browser/components/places/content/controller.js

@@ -168,7 +168,7 @@ PlacesController.prototype = {
       case "cmd_paste":
       case "placesCmd_paste":
         // If the clipboard contains a Places flavor it is definitely pasteable,
-        // otherwise we also allow pasting "text/unicode" and "text/x-moz-url" data.
+        // otherwise we also allow pasting "text/plain" and "text/x-moz-url" data.
         // We don't check if the data is valid here, because the clipboard may
         // contain very large blobs that would largely slowdown commands updating.
         // Of course later paste() should ignore any invalid data.
@@ -178,7 +178,7 @@ PlacesController.prototype = {
             [
               ...PlacesUIUtils.PLACES_FLAVORS,
               PlacesUtils.TYPE_X_MOZ_URL,
-              PlacesUtils.TYPE_UNICODE,
+              PlacesUtils.TYPE_PLAINTEXT,
             ],
             Ci.nsIClipboard.kGlobalClipboard
           )
@@ -1049,7 +1049,7 @@ PlacesController.prototype = {
 
     function addURIData(index) {
       addData(PlacesUtils.TYPE_X_MOZ_URL, index);
-      addData(PlacesUtils.TYPE_UNICODE, index);
+      addData(PlacesUtils.TYPE_PLAINTEXT, index);
       addData(PlacesUtils.TYPE_HTML, index);
     }
 
@@ -1131,7 +1131,7 @@ PlacesController.prototype = {
       { type: PlacesUtils.TYPE_X_MOZ_PLACE, entries: [] },
       { type: PlacesUtils.TYPE_X_MOZ_URL, entries: [] },
       { type: PlacesUtils.TYPE_HTML, entries: [] },
-      { type: PlacesUtils.TYPE_UNICODE, entries: [] },
+      { type: PlacesUtils.TYPE_PLAINTEXT, entries: [] },
     ];
 
     // Avoid handling descendants of a copied node, the transactions take care
@@ -1264,7 +1264,7 @@ PlacesController.prototype = {
     [
       PlacesUtils.TYPE_X_MOZ_PLACE,
       PlacesUtils.TYPE_X_MOZ_URL,
-      PlacesUtils.TYPE_UNICODE,
+      PlacesUtils.TYPE_PLAINTEXT,
     ].forEach(type => xferable.addDataFlavor(type));
 
     Services.clipboard.getData(xferable, Ci.nsIClipboard.kGlobalClipboard);
@@ -1494,13 +1494,6 @@ var PlacesControllerDragHelper = {
       }
     }
 
-    // If no supported flavor is found, check if data includes text/plain
-    // contents.  If so, request them as text/unicode, a conversion will happen
-    // automatically.
-    if (aFlavors.contains("text/plain")) {
-      return PlacesUtils.TYPE_UNICODE;
-    }
-
     return null;
   },
 
@@ -1623,7 +1616,7 @@ var PlacesControllerDragHelper = {
 
     // Following flavors may contain duplicated data.
     let duplicable = new Map();
-    duplicable.set(PlacesUtils.TYPE_UNICODE, new Set());
+    duplicable.set(PlacesUtils.TYPE_PLAINTEXT, new Set());
     duplicable.set(PlacesUtils.TYPE_X_MOZ_URL, new Set());
 
     // Collect all data from the DataTransfer before processing it, as the

browser/components/places/tests/browser/browser_toolbar_drop_text.js

@@ -133,7 +133,7 @@ add_task(async function test() {
   };
 
   // Simulate a bookmark drop for all of the mime types and effects.
-  let mimeTypes = ["text/plain", "text/unicode", "text/x-moz-url"];
+  let mimeTypes = ["text/plain", "text/x-moz-url"];
   let effects = ["move", "copy", "link"];
   for (let effect of effects) {
     for (let mimeType of mimeTypes) {

browser/components/textrecognition/tests/browser/head.js

@@ -19,11 +19,11 @@ function getTextFromClipboard() {
     Ci.nsITransferable
   );
   transferable.init(window.docShell.QueryInterface(Ci.nsILoadContext));
-  transferable.addDataFlavor("text/unicode");
+  transferable.addDataFlavor("text/plain");
   Services.clipboard.getData(transferable, Services.clipboard.kGlobalClipboard);
 
   const results = {};
-  transferable.getTransferData("text/unicode", results);
+  transferable.getTransferData("text/plain", results);
   return results.value.QueryInterface(Ci.nsISupportsString)?.data ?? "";
 }
 

browser/components/urlbar/UrlbarInput.sys.mjs

@@ -3604,7 +3604,7 @@ export class UrlbarInput {
     let title = this.window.gBrowser.contentTitle || href;
 
     event.dataTransfer.setData("text/x-moz-url", `${href}\n${title}`);
-    event.dataTransfer.setData("text/unicode", href);
+    event.dataTransfer.setData("text/plain", href);
     event.dataTransfer.setData("text/html", `<a href="${href}">${title}</a>`);
     event.dataTransfer.effectAllowed = "copyLink";
     event.stopPropagation();
@@ -3709,7 +3709,7 @@ function getDroppableData(event) {
     }
   }
   // Handle as text.
-  return event.dataTransfer.getData("text/unicode");
+  return event.dataTransfer.getData("text/plain");
 }
 
 /**

browser/components/urlbar/tests/browser/browser_primary_selection_safe_on_new_tab.js

@@ -60,7 +60,7 @@ add_task(async function() {
   }
 
   let primaryAsText = SpecialPowers.getClipboardData(
-    "text/unicode",
+    "text/plain",
     SpecialPowers.Ci.nsIClipboard.kSelectionClipboard
   );
   Assert.equal(primaryAsText, TEXT_FOR_PRIMARY);

browser/components/urlbar/tests/browser/browser_unitConversion.js

@@ -60,7 +60,7 @@ add_task(async function test_selectByKey() {
 
 function assertClipboard() {
   Assert.equal(
-    SpecialPowers.getClipboardData("text/unicode"),
+    SpecialPowers.getClipboardData("text/plain"),
     "100 cm",
     "The result of conversion is copied to clipboard"
   );

browser/components/urlbar/tests/browser/browser_urlbar_selection.js

@@ -83,7 +83,7 @@ function checkPrimarySelection(expectedVal = "") {
     )
   ) {
     let primaryAsText = SpecialPowers.getClipboardData(
-      "text/unicode",
+      "text/plain",
       SpecialPowers.Ci.nsIClipboard.kSelectionClipboard
     );
     Assert.equal(primaryAsText, expectedVal);

devtools/client/debugger/test/mochitest/browser_dbg-features-source-tree.js

@@ -110,7 +110,7 @@ add_task(async function testSimpleSourcesWithManualClickExpand() {
   info("Test the copy to clipboard context menu");
   const mathMinTreeNode = findSourceNodeWithText(dbg, "math.min.js");
   await triggerCopySourceContextMenu(dbg, mathMinTreeNode);
-  const clipboardData = SpecialPowers.getClipboardData("text/unicode");
+  const clipboardData = SpecialPowers.getClipboardData("text/plain");
   is(
     clipboardData,
     EXAMPLE_URL + "math.min.js",

devtools/client/inspector/changes/test/browser_changes_copy_all_changes.js

@@ -48,6 +48,6 @@ add_task(async function() {
 });
 
 function checkClipboardData(expected) {
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   return decodeURIComponent(actual).trim() === expected.trim();
 }

devtools/client/inspector/changes/test/browser_changes_copy_declaration.js

@@ -62,6 +62,6 @@ add_task(async function() {
 });
 
 function checkClipboardData(expected) {
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   return actual.trim() === expected.trim();
 }

devtools/client/inspector/changes/test/browser_changes_copy_rule.js

@@ -59,6 +59,6 @@ add_task(async function() {
 });
 
 function checkClipboardData(expected) {
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   return actual.trim() === expected.trim();
 }

devtools/client/inspector/computed/test/head.js

@@ -237,7 +237,7 @@ async function copySomeTextAndCheckClipboard(view, positions, expectedPattern) {
 }
 
 function checkClipboard(expectedPattern) {
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   const expectedRegExp = new RegExp(expectedPattern, "g");
   return expectedRegExp.test(actual);
 }
@@ -249,7 +249,7 @@ function failClipboardCheck(expectedPattern) {
   expectedPattern = expectedPattern.replace(/\\\(/g, "(");
   expectedPattern = expectedPattern.replace(/\\\)/g, ")");
 
-  let actual = SpecialPowers.getClipboardData("text/unicode");
+  let actual = SpecialPowers.getClipboardData("text/plain");
 
   // Trim the right hand side of our strings. This is because expectedPattern
   // accounts for windows sometimes adding a newline to our copied data.

devtools/client/inspector/rules/test/browser_rules_copy_styles.js

@@ -330,7 +330,7 @@ async function disableProperty(view, index) {
 }
 
 function checkClipboardData(expectedPattern) {
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   const expectedRegExp = new RegExp(expectedPattern, "g");
   return expectedRegExp.test(actual);
 }
@@ -342,7 +342,7 @@ function failedClipboard(expectedPattern) {
   expectedPattern = expectedPattern.replace(/\\\(/g, "(");
   expectedPattern = expectedPattern.replace(/\\\)/g, ")");
 
-  let actual = SpecialPowers.getClipboardData("text/unicode");
+  let actual = SpecialPowers.getClipboardData("text/plain");
 
   // Trim the right hand side of our strings. This is because expectedPattern
   // accounts for windows sometimes adding a newline to our copied data.

devtools/client/inspector/rules/test/browser_rules_select-and-copy-styles.js

@@ -182,7 +182,7 @@ async function checkCopyEditorValue(view) {
 }
 
 function checkClipboardData(expectedPattern) {
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   const expectedRegExp = new RegExp(expectedPattern, "g");
   return expectedRegExp.test(actual);
 }
@@ -194,7 +194,7 @@ function failedClipboard(expectedPattern) {
   expectedPattern = expectedPattern.replace(/\\\(/g, "(");
   expectedPattern = expectedPattern.replace(/\\\)/g, ")");
 
-  let actual = SpecialPowers.getClipboardData("text/unicode");
+  let actual = SpecialPowers.getClipboardData("text/plain");
 
   // Trim the right hand side of our strings. This is because expectedPattern
   // accounts for windows sometimes adding a newline to our copied data.

devtools/client/inspector/test/browser_inspector_highlighter-eyedropper-clipboard.js

@@ -43,11 +43,11 @@ add_task(async function() {
   ok(true, "The eyedropper is now hidden");
 
   info("Check that the clipboard still contains the copied color");
-  is(SpecialPowers.getClipboardData("text/unicode"), "#ff0000");
+  is(SpecialPowers.getClipboardData("text/plain"), "#ff0000");
 
   info("Replace the clipboard content with another text");
   SpecialPowers.clipboardCopyString("not-a-color");
-  is(SpecialPowers.getClipboardData("text/unicode"), "not-a-color");
+  is(SpecialPowers.getClipboardData("text/plain"), "not-a-color");
 
   info("Click on the page again, check the clipboard was not updated");
   await BrowserTestUtils.synthesizeMouseAtCenter(
@@ -57,7 +57,7 @@ add_task(async function() {
   );
   // Wait 500ms because nothing is observable when the test is successful.
   await wait(500);
-  is(SpecialPowers.getClipboardData("text/unicode"), "not-a-color");
+  is(SpecialPowers.getClipboardData("text/plain"), "not-a-color");
 
   finalize();
 });

devtools/client/netmonitor/src/har/test/browser_net_har_copy_all_as_har.js

@@ -155,7 +155,7 @@ async function testClearedRequests({ tab, monitor, toolbox }) {
     connector
   );
 
-  const jsonString = SpecialPowers.getClipboardData("text/unicode");
+  const jsonString = SpecialPowers.getClipboardData("text/plain");
   const har = JSON.parse(jsonString);
   is(har.log.entries.length, 2, "There must be two requests");
   is(
@@ -233,6 +233,6 @@ async function reloadAndCopyAllAsHar({
     connector
   );
 
-  const jsonString = SpecialPowers.getClipboardData("text/unicode");
+  const jsonString = SpecialPowers.getClipboardData("text/plain");
   return JSON.parse(jsonString);
 }

devtools/shared/platform/clipboard.js

@@ -15,12 +15,12 @@ function copyString(string) {
 }
 
 /**
- * Retrieve the current clipboard data matching the flavor "text/unicode".
+ * Retrieve the current clipboard data matching the flavor "text/plain".
  *
  * @return {String} Clipboard text content, null if no text clipboard data is available.
  */
 function getText() {
-  const flavor = "text/unicode";
+  const flavor = "text/plain";
 
   const xferable = Cc["@mozilla.org/widget/transferable;1"].createInstance(
     Ci.nsITransferable

dom/base/nsContentAreaDragDrop.cpp

@@ -692,7 +692,7 @@ nsresult DragDataProducer::Produce(DataTransfer* aDataTransfer, bool* aCanDrag,
     if (NS_SUCCEEDED(rv)) {
       data->GetData(mInfoString);
     }
-    rv = transferable->GetTransferData(kUnicodeMime, getter_AddRefs(supports));
+    rv = transferable->GetTransferData(kTextMime, getter_AddRefs(supports));
     data = do_QueryInterface(supports);
     NS_ENSURE_SUCCESS(rv, rv);  // require plain text at a minimum
     data->GetData(mTitleString);

dom/base/nsContentUtils.cpp

@@ -7785,9 +7785,7 @@ void nsContentUtils::CallOnAllRemoteChildren(
 bool nsContentUtils::IPCDataTransferItemHasKnownFlavor(
     const IPCDataTransferItem& aItem) {
   // Unknown types are converted to kCustomTypesMime.
-  // FIXME(bug 1776879) text/plain is converted to text/unicode still.
+  if (aItem.flavor().EqualsASCII(kCustomTypesMime)) {
-  if (aItem.flavor().EqualsASCII(kCustomTypesMime) ||
-      aItem.flavor().EqualsASCII(kUnicodeMime)) {
     return true;
   }
 

dom/base/nsCopySupport.cpp

@@ -93,7 +93,7 @@ static nsresult EncodeForTextUnicode(nsIDocumentEncoder& aEncoder,
   // html content with pre-wrap style : text/plain. Otherwise text/html. see
   // nsHTMLCopyEncoder::SetSelection
   nsAutoString mimeType;
-  mimeType.AssignLiteral(kUnicodeMime);
+  mimeType.AssignLiteral("text/unicode");
 
   // Do the first and potentially trial encoding as preformatted and raw.
   uint32_t flags = aAdditionalEncoderFlags |
@@ -171,7 +171,7 @@ static nsresult EncodeAsTextHTMLWithContext(
 }
 
 struct EncodedDocumentWithContext {
-  // When determening `mSerializationForTextUnicode`, `text/unicode` is passed
+  // When determining `mSerializationForTextUnicode`, `text/unicode` is passed
   // as mime type to the encoder. It uses this as a switch to decide whether to
   // encode the document as `text/html` or `text/plain`. It  is `true` iff
   // `text/html` was used.
@@ -274,14 +274,13 @@ static nsresult CreateTransferable(
 
     if (!aEncodedDocumentWithContext.mSerializationForTextUnicode.IsEmpty()) {
       // unicode text
-      // Add the unicode DataFlavor to the transferable
+      // Add the plain text DataFlavor to the transferable
       // If we didn't have this, then nsDataObj::GetData matches
-      // text/unicode against the kURLMime flavour which is not desirable
+      // text/plain against the kURLMime flavour which is not desirable
       // (eg. when pasting into Notepad)
-      rv =
+      rv = AppendString(
-          AppendString(aTransferable,
+          aTransferable,
-                       aEncodedDocumentWithContext.mSerializationForTextUnicode,
+          aEncodedDocumentWithContext.mSerializationForTextUnicode, kTextMime);
-                       kUnicodeMime);
       NS_ENSURE_SUCCESS(rv, rv);
     }
 
@@ -308,10 +307,9 @@ static nsresult CreateTransferable(
   } else {
     if (!aEncodedDocumentWithContext.mSerializationForTextUnicode.IsEmpty()) {
       // Add the unicode DataFlavor to the transferable
-      rv =
+      rv = AppendString(
-          AppendString(aTransferable,
+          aTransferable,
-                       aEncodedDocumentWithContext.mSerializationForTextUnicode,
+          aEncodedDocumentWithContext.mSerializationForTextUnicode, kTextMime);
-                       kUnicodeMime);
       NS_ENSURE_SUCCESS(rv, rv);
     }
   }
@@ -475,7 +473,7 @@ nsresult nsCopySupport::ImageCopy(nsIImageLoadingContent* aImageElement,
     NS_ENSURE_SUCCESS(rv, rv);
 
     // append the string to the transferable
-    rv = AppendString(trans, NS_ConvertUTF8toUTF16(location), kUnicodeMime);
+    rv = AppendString(trans, NS_ConvertUTF8toUTF16(location), kTextMime);
     NS_ENSURE_SUCCESS(rv, rv);
   }
 

dom/base/test/copypaste.js

@@ -50,8 +50,8 @@ async function testCopyPaste(isXHTML) {
     );
     if (!suppressUnicodeCheck) {
       ok(
-        clipboard.hasDataMatchingFlavors(["text/unicode"], 1),
+        clipboard.hasDataMatchingFlavors(["text/plain"], 1),
-        "check text/unicode"
+        "check text/plain"
       );
     }
     if (!suppressHTMLCheck) {
@@ -159,7 +159,7 @@ async function testCopyPaste(isXHTML) {
 
   await copyChildrenToClipboard("draggable");
   testSelectionToString("This is a draggable bit of text.");
-  testClipboardValue("text/unicode", "This is a draggable bit of text.");
+  testClipboardValue("text/plain", "This is a draggable bit of text.");
   testHtmlClipboardValue(
     "text/html",
     '<div id="draggable" title="title to have a long HTML line">This is a <em>draggable</em> bit of text.</div>'
@@ -168,7 +168,7 @@ async function testCopyPaste(isXHTML) {
 
   await copyChildrenToClipboard("alist");
   testSelectionToString(" bla\n\n    foo\n    bar\n\n");
-  testClipboardValue("text/unicode", " bla\n\n    foo\n    bar\n\n");
+  testClipboardValue("text/plain", " bla\n\n    foo\n    bar\n\n");
   testHtmlClipboardValue(
     "text/html",
     '<div id="alist">\n    bla\n    <ul>\n      <li>foo</li>\n      \n      <li>bar</li>\n    </ul>\n  </div>'
@@ -177,7 +177,7 @@ async function testCopyPaste(isXHTML) {
 
   await copyChildrenToClipboard("blist");
   testSelectionToString(" mozilla\n\n    foo\n    bar\n\n");
-  testClipboardValue("text/unicode", " mozilla\n\n    foo\n    bar\n\n");
+  testClipboardValue("text/plain", " mozilla\n\n    foo\n    bar\n\n");
   testHtmlClipboardValue(
     "text/html",
     '<div id="blist">\n    mozilla\n    <ol>\n      <li>foo</li>\n      \n      <li>bar</li>\n    </ol>\n  </div>'
@@ -187,7 +187,7 @@ async function testCopyPaste(isXHTML) {
   await copyChildrenToClipboard("clist");
   testSelectionToString(" mzla\n\n    foo\n        bazzinga!\n    bar\n\n");
   testClipboardValue(
-    "text/unicode",
+    "text/plain",
     " mzla\n\n    foo\n        bazzinga!\n    bar\n\n"
   );
   testHtmlClipboardValue(
@@ -198,7 +198,7 @@ async function testCopyPaste(isXHTML) {
 
   await copyChildrenToClipboard("div4");
   testSelectionToString(" Tt t t ");
-  testClipboardValue("text/unicode", " Tt t t ");
+  testClipboardValue("text/plain", " Tt t t ");
   if (isXHTML) {
     testHtmlClipboardValue(
       "text/html",
@@ -219,7 +219,7 @@ async function testCopyPaste(isXHTML) {
 
   await copyChildrenToClipboard("div5");
   testSelectionToString(" T     ");
-  testClipboardValue("text/unicode", " T     ");
+  testClipboardValue("text/plain", " T     ");
   if (isXHTML) {
     testHtmlClipboardValue(
       "text/html",
@@ -248,7 +248,7 @@ async function testCopyPaste(isXHTML) {
   testSelectionToString("");
   // START Disabled due to bug 564688
   if (false) {
-    testClipboardValue("text/unicode", "");
+    testClipboardValue("text/plain", "");
     testClipboardValue("text/html", "");
   }
   // END Disabled due to bug 564688
@@ -264,7 +264,7 @@ async function testCopyPaste(isXHTML) {
   testSelectionToString("");
   // START Disabled due to bug 564688
   if (false) {
-    testClipboardValue("text/unicode", "");
+    testClipboardValue("text/plain", "");
     testClipboardValue("text/html", "");
   }
   // END Disabled due to bug 564688
@@ -280,7 +280,7 @@ async function testCopyPaste(isXHTML) {
   testSelectionToString("");
   // START Disabled due to bug 564688
   if (false) {
-    testClipboardValue("text/unicode", "");
+    testClipboardValue("text/plain", "");
     testClipboardValue("text/html", "");
   }
   // END Disabled due to bug 564688
@@ -294,7 +294,7 @@ async function testCopyPaste(isXHTML) {
     suppressUnicodeCheckIfHidden
   );
   testSelectionToString("div9");
-  testClipboardValue("text/unicode", "div9");
+  testClipboardValue("text/plain", "div9");
   testHtmlClipboardValue("text/html", "div9");
   testInnerHTML("div9", "div9");
 
@@ -462,20 +462,20 @@ async function testCopyPaste(isXHTML) {
 
   await copyChildrenToClipboard("div13");
   testSelectionToString("__");
-  testClipboardValue("text/unicode", "__");
+  testClipboardValue("text/plain", "__");
   testHtmlClipboardValue("text/html", '<div id="div13">__</div>');
   testPasteText("__");
 
   // ============ converting cell boundaries to tabs in tables
 
   await copyToClipboard($("tr1"));
-  testClipboardValue("text/unicode", "foo\tbar");
+  testClipboardValue("text/plain", "foo\tbar");
 
   if (!isXHTML) {
     // ============ spanning multiple rows
 
     await copyRangeToClipboard($("tr2"), 0, $("tr3"), 0);
-    testClipboardValue("text/unicode", "1\t2\n3\t4\n");
+    testClipboardValue("text/plain", "1\t2\n3\t4\n");
     testHtmlClipboardValue(
       "text/html",
       '<table><tbody><tr id="tr2"><tr id="tr2"><td>1</td><td>2</td></tr><tr><td>3</td><td>4</td></tr><tr id="tr3"></tr></tr></tbody></table>'
@@ -487,7 +487,7 @@ async function testCopyPaste(isXHTML) {
     addRange($("tr2"), 0, $("tr2"), 2);
     addRange($("tr3"), 0, $("tr3"), 2);
     await copySelectionToClipboard();
-    testClipboardValue("text/unicode", "1\t2\n5\t6");
+    testClipboardValue("text/plain", "1\t2\n5\t6");
     testHtmlClipboardValue(
       "text/html",
       '<table><tbody><tr id="tr2"><td>1</td><td>2</td></tr><tr id="tr3"><td>5</td><td>6</td></tr></tbody></table>'
@@ -502,7 +502,7 @@ async function testCopyPaste(isXHTML) {
     $("div11").childNodes[1],
     2
   );
-  testClipboardValue("text/unicode", "Xdiv11");
+  testClipboardValue("text/plain", "Xdiv11");
   testHtmlClipboardValue("text/html", "<div><p>X<span>div</span>11</p></div>");
 
   await new Promise(resolve => {
@@ -520,7 +520,7 @@ async function testCopyPaste(isXHTML) {
     2
   );
 
-  testClipboardValue("text/unicode", "Xdiv12");
+  testClipboardValue("text/plain", "Xdiv12");
   testHtmlClipboardValue("text/html", "<div><p>X<span>div</span>12</p></div>");
   await new Promise(resolve => {
     setTimeout(resolve, 0);
@@ -539,18 +539,18 @@ async function testCopyPaste(isXHTML) {
 
     // Ruby annotation is included when selecting inside ruby.
     await copyRangeToClipboard(ruby1, 0, ruby1, 6);
-    testClipboardValue("text/unicode", "aabb(AABB)");
+    testClipboardValue("text/plain", "aabb(AABB)");
 
     // Ruby annotation is ignored when selecting across ruby.
     await copyRangeToClipboard(ruby1Container, 0, ruby1Container, 3);
-    testClipboardValue("text/unicode", "XaabbY");
+    testClipboardValue("text/plain", "XaabbY");
 
     // ... unless converter.html2txt.always_include_ruby is set
     await SpecialPowers.pushPrefEnv({
       set: [["converter.html2txt.always_include_ruby", true]],
     });
     await copyRangeToClipboard(ruby1Container, 0, ruby1Container, 3);
-    testClipboardValue("text/unicode", "Xaabb(AABB)Y");
+    testClipboardValue("text/plain", "Xaabb(AABB)Y");
     await SpecialPowers.popPrefEnv();
   }
 }

dom/base/test/test_bug116083.html

@@ -59,8 +59,8 @@ function hasExpectedFlavors() {
   var cb = Cc["@mozilla.org/widget/clipboard;1"].
            getService(Ci.nsIClipboard);
 
-  ok(cb.hasDataMatchingFlavors(["text/unicode"], cb.kGlobalClipboard),
+  ok(cb.hasDataMatchingFlavors(["text/plain"], cb.kGlobalClipboard),
-     "The clipboard has text/unicode");
+     "The clipboard has text/plain");
 
   ok(cb.hasDataMatchingFlavors(["text/html"], cb.kGlobalClipboard),
      "The clipboard has text/html");

dom/base/test/test_bug166235.html

@@ -50,7 +50,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=816298
     window.getSelection().selectAllChildren(document.getElementById(id));
     documentViewer.copySelection();
 
-    is(clipboard.hasDataMatchingFlavors(["text/unicode"], 1), true);
+    is(clipboard.hasDataMatchingFlavors(["text/plain"], 1), true);
     is(clipboard.hasDataMatchingFlavors(["text/html"], 1), true);
   }
   function getClipboardData(mime) {
@@ -110,7 +110,7 @@ var clipboardHTML = [
   '<p id=\"test5\">This<span style=\"user-select: all\"> text should</span> be copied.</p>',
 ];
 
-// expected results for clipboard text/unicode
+// expected results for clipboard text/plain
 var clipboardUnicode = [
   'This text should be copied.',
   'This text should be copied.',
@@ -145,7 +145,7 @@ for (var i = 0; i < originalStrings.length; i++) {
   copyChildrenToClipboard(id);
   is(window.getSelection().toString(), originalStrings[i], id + ' Selection.toString()');
   testHtmlClipboardValue("text/html", clipboardHTML[i], id);
-  testClipboardValue("text/unicode", clipboardUnicode[i], id);
+  testClipboardValue("text/plain", clipboardUnicode[i], id);
   testInnerHTML(id, innerHTMLStrings[i]);
   testPasteText(textareaStrings[i], id + '.innerHTML');
 }

dom/base/test/test_clipboard_nbsp.html

@@ -80,7 +80,7 @@ async function clipboardTextForElementId(aDomId, aExpectedString) {
     function setup() {
       synthesizeKey("C", {accelKey: true});
     },
-    "text/unicode");
+    "text/plain");
   return copiedText;
 }
 

dom/base/test/test_copyimage.html

@@ -57,15 +57,15 @@ function testCopyImage () {
 
   //--------- Let's check the content of the clipboard now.
 
-  // Does the clipboard contain text/unicode data ?
+  // Does the clipboard contain text/plain data ?
-  ok(clipboard.hasDataMatchingFlavors(["text/unicode"], clipboard.kGlobalClipboard), "clipboard contains unicode text");
+  ok(clipboard.hasDataMatchingFlavors(["text/plain"], clipboard.kGlobalClipboard), "clipboard contains unicode text");
   // Does the clipboard contain text/html data ?
   ok(clipboard.hasDataMatchingFlavors(["text/html"], clipboard.kGlobalClipboard), "clipboard contains html text");
   // Does the clipboard contain image data ?
   ok(clipboard.hasDataMatchingFlavors(["image/png"], clipboard.kGlobalClipboard), "clipboard contains image");
 
-  // Is the text/uncodie data correct ?
+  // Is the text/plain data correct ?
-  testClipboardValue('text/unicode', 'about:logo');
+  testClipboardValue('text/plain', 'about:logo');
   // Is the text/html data correct ?
   var expected = '<img id="logo" src="about:logo">';
   if (navigator.platform.includes("Win")) {

dom/base/test/test_copypaste.xhtml

@@ -6,10 +6,10 @@ This test is different from test_copypaste.html in two ways:
 
   1. The text/html clipboard flavor isn't tested, since nsCopySupport doesn't
      produce it for XHTML.
-  2. The text/unicode flavor isn't tested when the selection is in hidden
+  2. The text/plain flavor isn't tested when the selection is in hidden
      elements, since nsCopySupport doesn't produce text/plain for hidden
      elements, and unlike HTML, neither does it produce text/_moz_htmlcontext
-     and text/_moz_htmlinfo, which the clipboard converts to text/unicode.
+     and text/_moz_htmlinfo, which the clipboard converts to text/plain.
 -->
 <html xml:lang="en" xmlns="http://www.w3.org/1999/xhtml">
 <head>

dom/base/test/test_copypaste_disabled.html

@@ -82,7 +82,7 @@ waitUntilApzStable().then(async function() {
       let element = doc.getElementById(id);
       dragSelect(element, 0, 60);
       await copySelectionToClipboard();
-      testClipboardValue("text/unicode", element.value.substr(0, 3));
+      testClipboardValue("text/plain", element.value.substr(0, 3));
     }
   }
 

dom/base/test/useractivation/file_clipboard_common.js

@@ -91,7 +91,7 @@ function cutCopyAll(
         aSetup,
         aNext,
         aNext,
-        "text/unicode",
+        "text/plain",
         WATCH_TIMEOUT,
         true
       );

dom/events/Clipboard.cpp

@@ -97,7 +97,7 @@ void Clipboard::ReadRequest::Answer() {
               // Mandatory data types defined in
               // https://w3c.github.io/clipboard-apis/#mandatory-data-types-x
               AutoTArray<nsCString, 3>{nsDependentCString(kHTMLMime),
-                                       nsDependentCString(kUnicodeMime),
+                                       nsDependentCString(kTextMime),
                                        nsDependentCString(kPNGImageMime)},
               nsIClipboard::kGlobalClipboard)
           ->Then(
@@ -123,10 +123,7 @@ void Clipboard::ReadRequest::Answer() {
 
                   RefPtr<ClipboardItem::ItemEntry> entry =
                       MakeRefPtr<ClipboardItem::ItemEntry>(
-                          format.EqualsLiteral(kUnicodeMime)
+                          NS_ConvertUTF8toUTF16(format), format);
-                              ? NS_ConvertUTF8toUTF16(kTextMime)
-                              : NS_ConvertUTF8toUTF16(format),
-                          format);
                   entry->LoadData(*global, *trans);
                   entries.AppendElement(std::move(entry));
                 }
@@ -152,7 +149,7 @@ void Clipboard::ReadRequest::Answer() {
       }
 
       trans->Init(nullptr);
-      trans->AddDataFlavor(kUnicodeMime);
+      trans->AddDataFlavor(kTextMime);
       clipboardService->AsyncGetData(trans, nsIClipboard::kGlobalClipboard)
           ->Then(
               GetMainThreadSerialEventTarget(), __func__,
@@ -160,7 +157,7 @@ void Clipboard::ReadRequest::Answer() {
               [trans, p]() {
                 nsCOMPtr<nsISupports> data;
                 nsresult rv =
-                    trans->GetTransferData(kUnicodeMime, getter_AddRefs(data));
+                    trans->GetTransferData(kTextMime, getter_AddRefs(data));
 
                 nsAutoString str;
                 if (!NS_WARN_IF(NS_FAILED(rv))) {
@@ -681,7 +678,7 @@ already_AddRefed<Promise> Clipboard::WriteText(const nsAString& aData,
 
   nsTArray<RefPtr<ClipboardItem::ItemEntry>> items;
   items.AppendElement(MakeRefPtr<ClipboardItem::ItemEntry>(
-      NS_LITERAL_STRING_FROM_CSTRING(kTextMime), nsLiteralCString(kUnicodeMime),
+      NS_LITERAL_STRING_FROM_CSTRING(kTextMime), nsLiteralCString(kTextMime),
       std::move(data)));
 
   nsTArray<OwningNonNull<ClipboardItem>> sequence;

dom/events/ClipboardItem.cpp

@@ -22,15 +22,7 @@ NS_IMPL_CYCLE_COLLECTION(ClipboardItem::ItemEntry, mData,
 
 ClipboardItem::ItemEntry::ItemEntry(const nsAString& aType,
                                     const nsACString& aFormat)
-    : mType(aType), mFormat(aFormat) {
+    : mType(aType), mFormat(aFormat) {}
-  // XXX https://bugzilla.mozilla.org/show_bug.cgi?id=1776879.
-  // In most of cases, the mType and mFormat are the same, execpt for plain
-  // text. We expose it as "text/plain" to the web, but we use "text/unicode"
-  // internally to retrieve from system clipboard.
-  MOZ_ASSERT_IF(
-      !mType.Equals(NS_ConvertUTF8toUTF16(mFormat)),
-      mType.EqualsLiteral(kTextMime) && mFormat.EqualsLiteral(kUnicodeMime));
-}
 
 void ClipboardItem::ItemEntry::SetData(already_AddRefed<Blob>&& aBlob) {
   // XXX maybe we could consider adding a method to check whether the union
@@ -190,9 +182,7 @@ already_AddRefed<ClipboardItem> ClipboardItem::Constructor(
 
   nsTArray<RefPtr<ItemEntry>> items;
   for (const auto& entry : aItems.Entries()) {
-    nsAutoCString format = entry.mKey.EqualsLiteral(kTextMime)
+    nsAutoCString format = NS_ConvertUTF16toUTF8(entry.mKey);
-                               ? nsAutoCString(kUnicodeMime)
-                               : NS_ConvertUTF16toUTF8(entry.mKey);
     items.AppendElement(
         MakeRefPtr<ItemEntry>(entry.mKey, format, entry.mValue));
   }

dom/events/DataTransfer.cpp

@@ -622,8 +622,8 @@ already_AddRefed<DataTransfer> DataTransfer::MozCloneForEvent(
 // The order of the types matters. `kFileMime` needs to be one of the first two
 // types.
 static const char* kNonPlainTextExternalFormats[] = {
-    kCustomTypesMime, kFileMime,    kHTMLMime,     kRTFMime,  kURLMime,
+    kCustomTypesMime, kFileMime, kHTMLMime,     kRTFMime,  kURLMime,
-    kURLDataMime,     kUnicodeMime, kPNGImageMime, kPDFJSMime};
+    kURLDataMime,     kTextMime, kPNGImageMime, kPDFJSMime};
 
 /* static */
 void DataTransfer::GetExternalClipboardFormats(const int32_t& aWhichClipboard,
@@ -643,12 +643,12 @@ void DataTransfer::GetExternalClipboardFormats(const int32_t& aWhichClipboard,
 
   if (aPlainTextOnly) {
     bool hasType;
-    AutoTArray<nsCString, 1> unicodeMime = {nsDependentCString(kUnicodeMime)};
+    AutoTArray<nsCString, 1> textMime = {nsDependentCString(kTextMime)};
-    nsresult rv = clipboard->HasDataMatchingFlavors(unicodeMime,
+    nsresult rv =
-                                                    aWhichClipboard, &hasType);
+        clipboard->HasDataMatchingFlavors(textMime, aWhichClipboard, &hasType);
     NS_SUCCEEDED(rv);
     if (hasType) {
-      aResult->AppendElement(kUnicodeMime);
+      aResult->AppendElement(kTextMime);
     }
     return;
   }
@@ -685,9 +685,9 @@ void DataTransfer::GetExternalTransferableFormats(
   aTransferable->FlavorsTransferableCanExport(flavors);
 
   if (aPlainTextOnly) {
-    auto index = flavors.IndexOf(nsLiteralCString(kUnicodeMime));
+    auto index = flavors.IndexOf(nsLiteralCString(kTextMime));
     if (index != flavors.NoIndex) {
-      aResult->AppendElement(nsLiteralCString(kUnicodeMime));
+      aResult->AppendElement(nsLiteralCString(kTextMime));
     }
     return;
   }
@@ -1084,27 +1084,20 @@ already_AddRefed<nsITransferable> DataTransfer::GetTransferable(
           continue;
         }
 
-        // The underlying drag code uses text/unicode, so use that instead of
+        NS_ConvertUTF16toUTF8 format(type);
-        // text/plain
-        const char* format;
-        NS_ConvertUTF16toUTF8 utf8format(type);
-        if (utf8format.EqualsLiteral(kTextMime)) {
-          format = kUnicodeMime;
-        } else {
-          format = utf8format.get();
-        }
 
         // If a converter is set for a format, set the converter for the
         // transferable and don't add the item
         nsCOMPtr<nsIFormatConverter> converter =
             do_QueryInterface(convertedData);
         if (converter) {
-          transferable->AddDataFlavor(format);
+          transferable->AddDataFlavor(format.get());
           transferable->SetConverter(converter);
           continue;
         }
 
-        nsresult rv = transferable->SetTransferData(format, convertedData);
+        nsresult rv =
+            transferable->SetTransferData(format.get(), convertedData);
         if (NS_FAILED(rv)) {
           return nullptr;
         }
@@ -1225,7 +1218,7 @@ void DataTransfer::SetDataWithPrincipalFromOtherProcess(
 
 void DataTransfer::GetRealFormat(const nsAString& aInFormat,
                                  nsAString& aOutFormat) const {
-  // treat text/unicode as equivalent to text/plain
+  // For compatibility, treat text/unicode as equivalent to text/plain
   nsAutoString lowercaseFormat;
   nsContentUtils::ASCIIToLower(aInFormat, lowercaseFormat);
   if (lowercaseFormat.EqualsLiteral("text") ||
@@ -1248,7 +1241,7 @@ nsresult DataTransfer::CacheExternalData(const char* aFormat, uint32_t aIndex,
   ErrorResult rv;
   RefPtr<DataTransferItem> item;
 
-  if (strcmp(aFormat, kUnicodeMime) == 0) {
+  if (strcmp(aFormat, kTextMime) == 0) {
     item = mItems->SetDataWithPrincipal(u"text/plain"_ns, nullptr, aIndex,
                                         aPrincipal, false, aHidden, rv);
     if (NS_WARN_IF(rv.Failed())) {
@@ -1298,8 +1291,8 @@ void DataTransfer::CacheExternalDragFormats() {
   // XXXndeakin there are some other formats but those are platform specific.
   // NOTE: kFileMime must have index 0
   // TODO: should this be `kNonPlainTextExternalFormats` instead?
-  static const char* formats[] = {kFileMime,    kHTMLMime,    kURLMime,
+  static const char* formats[] = {kFileMime,    kHTMLMime, kURLMime,
-                                  kURLDataMime, kUnicodeMime, kPNGImageMime};
+                                  kURLDataMime, kTextMime, kPNGImageMime};
 
   uint32_t count;
   dragSession->GetNumDropItems(&count);
@@ -1350,10 +1343,10 @@ void DataTransfer::CacheExternalClipboardFormats(bool aPlainTextOnly) {
   }
 
   if (aPlainTextOnly) {
-    // The only thing that will be in types is kUnicodeMime
+    // The only thing that will be in types is kTextMime
     MOZ_ASSERT(typesArray.IsEmpty() || typesArray.Length() == 1);
     if (typesArray.Length() == 1) {
-      CacheExternalData(kUnicodeMime, 0, sysPrincipal, false);
+      CacheExternalData(kTextMime, 0, sysPrincipal, false);
     }
     return;
   }

dom/events/DataTransfer.h

@@ -365,7 +365,7 @@ class DataTransfer final : public nsISupports, public nsWrapperCache {
                  DataTransfer** aResult);
 
   // converts some formats used for compatibility in aInFormat into aOutFormat.
-  // Text and text/unicode become text/plain, and URL becomes text/uri-list
+  // Text becomes text/plain, and URL becomes text/uri-list
   void GetRealFormat(const nsAString& aInFormat, nsAString& aOutFormat) const;
 
   static bool PrincipalMaySetData(const nsAString& aFormat, nsIVariant* aData,

dom/events/DataTransferItem.cpp

@@ -150,9 +150,7 @@ void DataTransferItem::FillInExternalData() {
 
   NS_ConvertUTF16toUTF8 utf8format(mType);
   const char* format = utf8format.get();
-  if (strcmp(format, "text/plain") == 0) {
+  if (strcmp(format, "text/uri-list") == 0) {
-    format = kUnicodeMime;
-  } else if (strcmp(format, "text/uri-list") == 0) {
     format = kURLDataMime;
   }
 

dom/events/test/clipboard/test_async_clipboard.xhtml

@@ -24,10 +24,6 @@
     "resource://gre/modules/PlacesUtils.jsm"
   );
 
-  // Some of the clipboard code requires reading or writing "text/unicode" when
-  // actually "text/plain" is desired.
-  const kTextUnicodeMimeType = "text/unicode";
-
   const kTextPlainMimeType = "text/plain";
 
   function clearClipboard() {
@@ -38,7 +34,7 @@
     let expected = "x";
     await SimpleTest.promiseClipboardChange(expected, () => {
       SpecialPowers.clipboardCopyString(expected);
-    }, kTextUnicodeMimeType);
+    }, kTextPlainMimeType);
     let items = await navigator.clipboard.read();
     is(items.length, 1, "read() read exactly one item");
     const actual = await items[0].getType(kTextPlainMimeType).then(blob => blob.text());
@@ -54,7 +50,7 @@
     // eslint-disable-next-line no-undef
     let item = new ClipboardItem({[kTextPlainMimeType]: expected});
     await navigator.clipboard.write([item]);
-    let actual = SpecialPowers.getClipboardData(kTextUnicodeMimeType);
+    let actual = SpecialPowers.getClipboardData(kTextPlainMimeType);
     is(actual, expected, "write() wrote the right thing");
   }
 
@@ -62,7 +58,7 @@
     let expected = "x";
     await SimpleTest.promiseClipboardChange(expected, () => {
       SpecialPowers.clipboardCopyString(expected);
-    }, kTextUnicodeMimeType);
+    }, kTextPlainMimeType);
     let actual = await navigator.clipboard.readText();
     is(actual, expected, "readText() read the right thing");
   }
@@ -74,7 +70,7 @@
 
     let expected = "x";
     await navigator.clipboard.writeText(expected);
-    let actual = SpecialPowers.getClipboardData(kTextUnicodeMimeType);
+    let actual = SpecialPowers.getClipboardData(kTextPlainMimeType);
     is(actual, expected, "writeText() wrote the right thing");
   }
 

dom/events/test/test_bug1327798.html

@@ -26,8 +26,8 @@ SimpleTest.waitForFocus(() => {
   //--------- now check the content of the clipboard
   var clipboard = SpecialPowers.Cc["@mozilla.org/widget/clipboard;1"]
                                .getService(SpecialPowers.Ci.nsIClipboard);
-  // does the clipboard contain text/unicode data ?
+  // does the clipboard contain text/plain data ?
-  ok(clipboard.hasDataMatchingFlavors(["text/unicode"], clipboard.kGlobalClipboard),
+  ok(clipboard.hasDataMatchingFlavors(["text/plain"], clipboard.kGlobalClipboard),
      "clipboard contains unicode text");
   // does the clipboard contain text/html data ?
   ok(clipboard.hasDataMatchingFlavors(["text/html"], clipboard.kGlobalClipboard),

dom/events/test/test_dragstart.html

@@ -142,13 +142,14 @@ function doDragStartSelection(event)
   is(dt.getData("text/html"), "<div id=\"draggable\" ondragstart=\"doDragStartSelection(event)\">This is a <em>draggable</em> bit of text.</div>",
      "initial selection text/html");
 
-  // text/unicode and Text are available for compatibility. They retrieve the
+  // text/plain and Text are available for compatibility. They retrieve the
-  // text/plain data
+  // text/plain data. text/unicode is also for compatibility and retreives the plain text.
-  is(dt.getData("text/unicode"), "This is a draggable bit of text.", "initial selection text/unicode");
+  is(dt.getData("text/plain"), "This is a draggable bit of text.", "initial selection text/plain");
   is(dt.getData("Text"), "This is a draggable bit of text.", "initial selection Text");
   is(dt.getData("TEXT"), "This is a draggable bit of text.", "initial selection TEXT");
-  is(dt.getData("text/UNICODE"), "This is a draggable bit of text.", "initial selection text/UNICODE"); 
+  is(dt.getData("text/PLAIN"), "This is a draggable bit of text.", "initial selection text/PLAIN");
-
+  is(dt.getData("text/unicode"), "This is a draggable bit of text.", "initial selection text/unicode");
+  
   is(SpecialPowers.wrap(dt).mozItemCount, 1, "initial selection item count");
 
   dt.clearData("text/plain");

dom/events/test/test_paste_image.html

@@ -88,8 +88,8 @@
     //--------- now check the content of the clipboard
     var clipboard = SpecialPowers.Cc["@mozilla.org/widget/clipboard;1"]
                                  .getService(SpecialPowers.Ci.nsIClipboard);
-    // does the clipboard contain text/unicode data ?
+    // does the clipboard contain text/plain data ?
-    ok(clipboard.hasDataMatchingFlavors(["text/unicode"], clipboard.kGlobalClipboard),
+    ok(clipboard.hasDataMatchingFlavors(["text/plain"], clipboard.kGlobalClipboard),
        "clipboard contains unicode text");
     // does the clipboard contain text/html data ?
     ok(clipboard.hasDataMatchingFlavors(["text/html"], clipboard.kGlobalClipboard),

dom/ipc/tests/browser_child_clipboard_restricted.js

@@ -23,8 +23,8 @@ add_task(async function() {
     trans.addDataFlavor("text/unknown");
     trans.setTransferData("text/unknown", string);
 
-    trans.addDataFlavor("text/unicode");
+    trans.addDataFlavor("text/plain");
-    trans.setTransferData("text/unicode", string);
+    trans.setTransferData("text/plain", string);
 
     // Write to clipboard.
     Services.clipboard.setData(trans, null, Ci.nsIClipboard.kGlobalClipboard);
@@ -34,7 +34,7 @@ add_task(async function() {
   for (var i = 0; i < 20; i++) {
     if (
       Services.clipboard.hasDataMatchingFlavors(
-        ["text/unicode"],
+        ["text/plain"],
         Services.clipboard.kGlobalClipboard
       )
     ) {
@@ -57,16 +57,16 @@ add_task(async function() {
 
   ok(
     Services.clipboard.hasDataMatchingFlavors(
-      ["text/unicode"],
+      ["text/plain"],
       Services.clipboard.kGlobalClipboard
     ),
-    "clipboard should have text/unicode"
+    "clipboard should have text/plain"
   );
 
   is(
-    readClipboard("text/unicode"),
+    readClipboard("text/plain"),
     "blablabla",
-    "matching string for text/unicode"
+    "matching string for text/plain"
   );
 
   ok(

dom/serializers/nsDocumentEncoder.cpp

@@ -1551,7 +1551,7 @@ nsHTMLCopyEncoder::Init(Document* aDocument, const nsAString& aMimeType,
   mIsCopying = true;
   mDocument = aDocument;
 
-  // Hack, hack! Traditionally, the caller passes text/unicode, which is
+  // Hack, hack! Traditionally, the caller passes text/plain, which is
   // treated as "guess text/html or text/plain" in this context. (It has a
   // different meaning in other contexts. Sigh.) From now on, "text/plain"
   // means forcing text/plain instead of guessing.

dom/tests/mochitest/general/test_paste_selection.html

@@ -20,8 +20,8 @@ var supportsSelectionClipboard = SpecialPowers.supportsSelectionClipboard();
 function checkSelectionClipboardText(count)
 {
   if ((!supportsSelectionClipboard ||
-       SpecialPowers.getClipboardData("text/unicode", SpecialPowers.Ci.nsIClipboard.kSelectionClipboard) == "COPY TEXT") &&
+       SpecialPowers.getClipboardData("text/plain", SpecialPowers.Ci.nsIClipboard.kSelectionClipboard) == "COPY TEXT") &&
-      SpecialPowers.getClipboardData("text/unicode", SpecialPowers.Ci.nsIClipboard.kGlobalClipboard) == "CLIPBOARD") {
+      SpecialPowers.getClipboardData("text/plain", SpecialPowers.Ci.nsIClipboard.kGlobalClipboard) == "CLIPBOARD") {
     pasteArea();
     return;
   }

dom/tests/mochitest/general/window_clipboard_events.html

@@ -102,7 +102,7 @@ async function reset() {
 }
 
 function getClipboardText() {
-  return SpecialPowers.getClipboardData("text/unicode");
+  return SpecialPowers.getClipboardData("text/plain");
 }
 
 function getHTMLEditor() {

dom/tests/mochitest/keyhandling/test_editor.xhtml

@@ -190,7 +190,7 @@
       info("cut");
       await synthesizeKey(VK.X, { accelKey: true }, "x");
       await checkElement(editor, 0, "", "");
-      let text = SpecialPowers.getClipboardData("text/unicode");
+      let text = SpecialPowers.getClipboardData("text/plain");
       is(text, "Test text", "Should have cut to the clipboard");
       SpecialPowers.clipboardCopyString("New text");
 

dom/tests/mochitest/keyhandling/test_input.html

@@ -146,7 +146,7 @@ async function startTest() {
   info("cut");
   await synthesizeKey(VK.X, { accelKey: true }, "x", "input");
   await checkElement(input, 0, 0, "");
-  let text = SpecialPowers.getClipboardData("text/unicode");
+  let text = SpecialPowers.getClipboardData("text/plain");
   is(text, "Test text", "Should have cut to the clipboard");
   SpecialPowers.clipboardCopyString("New text");
 

dom/tests/mochitest/keyhandling/test_textarea.html

@@ -146,7 +146,7 @@ async function startTest() {
   info("cut");
   await synthesizeKey(VK.X, { accelKey: true }, "x", "input");
   await checkElement(input, 0, 0, "");
-  let text = SpecialPowers.getClipboardData("text/unicode");
+  let text = SpecialPowers.getClipboardData("text/plain");
   is(text, "Test text", "Should have cut to the clipboard");
   SpecialPowers.clipboardCopyString("New text");
 

editor/libeditor/EditorUtils.cpp

@@ -221,10 +221,10 @@ EditorUtils::CreateTransferableForPlainText(const Document& aDocument) {
   NS_WARNING_ASSERTION(NS_SUCCEEDED(rvIgnored),
                        "nsITransferable::Init() failed, but ignored");
 
-  rvIgnored = transferable->AddDataFlavor(kUnicodeMime);
+  rvIgnored = transferable->AddDataFlavor(kTextMime);
   NS_WARNING_ASSERTION(
       NS_SUCCEEDED(rvIgnored),
-      "nsITransferable::AddDataFlavor(kUnicodeMime) failed, but ignored");
+      "nsITransferable::AddDataFlavor(kTextMime) failed, but ignored");
   rvIgnored = transferable->AddDataFlavor(kMozTextInternal);
   NS_WARNING_ASSERTION(
       NS_SUCCEEDED(rvIgnored),

editor/libeditor/EditorUtils.h

@@ -432,7 +432,7 @@ class EditorUtils final {
                                  const nsINode& aParentNode, uint32_t aOffset);
 
   /**
-   * Create an nsITransferable instance which has kUnicodeMime and
+   * Create an nsITransferable instance which has kTextMime and
    * kMozTextInternal flavors.
    */
   static Result<nsCOMPtr<nsITransferable>, nsresult>

editor/libeditor/HTMLEditorDataTransfer.cpp

@@ -1463,10 +1463,10 @@ void HTMLEditor::HTMLTransferablePreparer::AddDataFlavorsInBestOrder(
         break;
     }
   }
-  DebugOnly<nsresult> rvIgnored = aTransferable.AddDataFlavor(kUnicodeMime);
+  DebugOnly<nsresult> rvIgnored = aTransferable.AddDataFlavor(kTextMime);
   NS_WARNING_ASSERTION(
       NS_SUCCEEDED(rvIgnored),
-      "nsITransferable::AddDataFlavor(kUnicodeMime) failed, but ignored");
+      "nsITransferable::AddDataFlavor(kTextMime) failed, but ignored");
   rvIgnored = aTransferable.AddDataFlavor(kMozTextInternal);
   NS_WARNING_ASSERTION(
       NS_SUCCEEDED(rvIgnored),
@@ -2035,7 +2035,7 @@ nsresult HTMLEditor::InsertFromTransferableAtSelection(
       }
     }
     if (bestFlavor.EqualsLiteral(kHTMLMime) ||
-        bestFlavor.EqualsLiteral(kUnicodeMime) ||
+        bestFlavor.EqualsLiteral(kTextMime) ||
         bestFlavor.EqualsLiteral(kMozTextInternal)) {
       nsAutoString stuffToPaste;
       if (!GetString(genericDataObj, stuffToPaste)) {
@@ -2542,8 +2542,8 @@ nsresult HTMLEditor::PasteNoFormattingAsAction(int32_t aSelectionType,
 // The following arrays contain the MIME types that we can paste. The arrays
 // are used by CanPaste() and CanPasteTransferable() below.
 
-static const char* textEditorFlavors[] = {kUnicodeMime};
+static const char* textEditorFlavors[] = {kTextMime};
-static const char* textHtmlEditorFlavors[] = {kUnicodeMime,   kHTMLMime,
+static const char* textHtmlEditorFlavors[] = {kTextMime,      kHTMLMime,
                                               kJPEGImageMime, kJPGImageMime,
                                               kPNGImageMime,  kGIFImageMime};
 
@@ -2792,10 +2792,10 @@ nsresult HTMLEditor::PasteAsPlaintextQuotation(int32_t aSelectionType) {
                        "nsITransferable::Init() failed, but ignored");
 
   // We only handle plaintext pastes here
-  rvIgnored = transferable->AddDataFlavor(kUnicodeMime);
+  rvIgnored = transferable->AddDataFlavor(kTextMime);
   NS_WARNING_ASSERTION(
       NS_SUCCEEDED(rvIgnored),
-      "nsITransferable::AddDataFlavor(kUnicodeMime) failed, but ignored");
+      "nsITransferable::AddDataFlavor(kTextMime) failed, but ignored");
 
   // Get the Data from the clipboard
   rvIgnored = clipboard->GetData(transferable, aSelectionType);
@@ -2813,7 +2813,7 @@ nsresult HTMLEditor::PasteAsPlaintextQuotation(int32_t aSelectionType) {
     return rv;
   }
 
-  if (!flavor.EqualsLiteral(kUnicodeMime)) {
+  if (!flavor.EqualsLiteral(kTextMime)) {
     return NS_OK;
   }
 

editor/libeditor/TextEditor.cpp

@@ -593,8 +593,7 @@ nsresult TextEditor::PasteAsQuotationAsAction(int32_t aClipboardType,
     return EditorBase::ToGenericNSResult(rv);
   }
 
-  if (!flav.EqualsLiteral(kUnicodeMime) &&
+  if (!flav.EqualsLiteral(kTextMime) && !flav.EqualsLiteral(kMozTextInternal)) {
-      !flav.EqualsLiteral(kMozTextInternal)) {
     return NS_OK;
   }
 

editor/libeditor/TextEditorDataTransfer.cpp

@@ -53,7 +53,7 @@ nsresult TextEditor::InsertTextFromTransferable(
   NS_WARNING_ASSERTION(
       NS_SUCCEEDED(rv),
       "nsITransferable::GetAnyDataTransferData() failed, but ignored");
-  if (NS_SUCCEEDED(rv) && (bestFlavor.EqualsLiteral(kUnicodeMime) ||
+  if (NS_SUCCEEDED(rv) && (bestFlavor.EqualsLiteral(kTextMime) ||
                            bestFlavor.EqualsLiteral(kMozTextInternal))) {
     AutoTransactionsConserveSelection dontChangeMySelection(*this);
 
@@ -271,8 +271,7 @@ bool TextEditor::CanPaste(int32_t aClipboardType) const {
   }
 
   // the flavors that we can deal with
-  AutoTArray<nsCString, 1> textEditorFlavors = {
+  AutoTArray<nsCString, 1> textEditorFlavors = {nsDependentCString(kTextMime)};
-      nsDependentCString(kUnicodeMime)};
 
   bool haveFlavors;
   rv = clipboard->HasDataMatchingFlavors(textEditorFlavors, aClipboardType,
@@ -294,10 +293,9 @@ bool TextEditor::CanPasteTransferable(nsITransferable* aTransferable) {
   }
 
   nsCOMPtr<nsISupports> data;
-  nsresult rv =
+  nsresult rv = aTransferable->GetTransferData(kTextMime, getter_AddRefs(data));
-      aTransferable->GetTransferData(kUnicodeMime, getter_AddRefs(data));
   NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
-                       "nsITransferable::GetTransferData(kUnicodeMime) failed");
+                       "nsITransferable::GetTransferData(kTextMime) failed");
   return NS_SUCCEEDED(rv) && data;
 }
 

editor/libeditor/tests/test_bug525389.html

@@ -60,7 +60,7 @@ async function runTest() {
     if (asHTML) {
       trans.addDataFlavor("text/html");
     } else {
-      trans.addDataFlavor("text/unicode");
+      trans.addDataFlavor("text/plain");
     }
     var clip = SpecialPowers.Services.clipboard;
     clip.getData(trans, Ci.nsIClipboard.kGlobalClipboard);
@@ -103,9 +103,9 @@ async function runTest() {
   //     ssData.data = doc.body.innerHTML;
   //     trans.setTransferData("text/html", ssData);
   //   } else {
-  //     trans.addDataFlavor("text/unicode");
+  //     trans.addDataFlavor("text/plain");
   //     ssData.data = doc.body.innerHTML;
-  //     trans.setTransferData("text/unicode", ssData);
+  //     trans.setTransferData("text/plain", ssData);
   //   }
   //
   //   return trans;

editor/libeditor/tests/test_bug795418-2.html

@@ -76,7 +76,7 @@ SimpleTest.waitForFocus(function() {
       SimpleTest.finish();
     },
     // TODO: bug 1686012
-    SpecialPowers.isHeadless ? "text/unicode" : "text/html"
+    SpecialPowers.isHeadless ? "text/plain" : "text/html"
   );
 });
 

editor/libeditor/tests/test_cut_copy_password.html

@@ -37,15 +37,15 @@ SimpleTest.waitForFocus(async () => {
   input.setSelectionRange(0, 6);
   ok(true, "Trying to copy masked password...");
   await copyToClipboard(null);
-  isnot(SpecialPowers.getClipboardData("text/unicode"), "abcdef",
+  isnot(SpecialPowers.getClipboardData("text/plain"), "abcdef",
         "Copying masked password shouldn't copy raw value into the clipboard");
-  isnot(SpecialPowers.getClipboardData("text/unicode"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
+  isnot(SpecialPowers.getClipboardData("text/plain"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
         "Copying masked password shouldn't copy masked value into the clipboard");
   ok(true, "Trying to cut masked password...");
   await cutToClipboard(null);
-  isnot(SpecialPowers.getClipboardData("text/unicode"), "abcdef",
+  isnot(SpecialPowers.getClipboardData("text/plain"), "abcdef",
         "Cutting masked password shouldn't copy raw value into the clipboard");
-  isnot(SpecialPowers.getClipboardData("text/unicode"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
+  isnot(SpecialPowers.getClipboardData("text/plain"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
         "Cutting masked password shouldn't copy masked value into the clipboard");
   is(input.value, "abcdef",
      "Cutting masked password shouldn't modify the value");
@@ -54,19 +54,19 @@ SimpleTest.waitForFocus(async () => {
   input.setSelectionRange(0, 6);
   ok(true, "Trying to copy partially masked password...");
   await copyToClipboard(null);
-  isnot(SpecialPowers.getClipboardData("text/unicode"), "abcdef",
+  isnot(SpecialPowers.getClipboardData("text/plain"), "abcdef",
         "Copying partially masked password shouldn't copy raw value into the clipboard");
-  isnot(SpecialPowers.getClipboardData("text/unicode"), `${kMask}${kMask}cd${kMask}${kMask}`,
+  isnot(SpecialPowers.getClipboardData("text/plain"), `${kMask}${kMask}cd${kMask}${kMask}`,
         "Copying partially masked password shouldn't copy partially masked value into the clipboard");
-  isnot(SpecialPowers.getClipboardData("text/unicode"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
+  isnot(SpecialPowers.getClipboardData("text/plain"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
         "Copying partially masked password shouldn't copy masked value into the clipboard");
   ok(true, "Trying to cut partially masked password...");
   await cutToClipboard(null);
-  isnot(SpecialPowers.getClipboardData("text/unicode"), "abcdef",
+  isnot(SpecialPowers.getClipboardData("text/plain"), "abcdef",
         "Cutting partially masked password shouldn't copy raw value into the clipboard");
-  isnot(SpecialPowers.getClipboardData("text/unicode"), `${kMask}${kMask}cd${kMask}${kMask}`,
+  isnot(SpecialPowers.getClipboardData("text/plain"), `${kMask}${kMask}cd${kMask}${kMask}`,
         "Cutting partially masked password shouldn't copy partially masked value into the clipboard");
-  isnot(SpecialPowers.getClipboardData("text/unicode"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
+  isnot(SpecialPowers.getClipboardData("text/plain"), `${kMask}${kMask}${kMask}${kMask}${kMask}${kMask}`,
         "Cutting partially masked password shouldn't copy masked value into the clipboard");
   is(input.value, "abcdef",
      "Cutting partially masked password shouldn't modify the value");

editor/libeditor/tests/test_password_paste.html

@@ -34,7 +34,7 @@ function pasteText(str) {
   let s = Cc["@mozilla.org/supports-string;1"].
           createInstance(Ci.nsISupportsString);
   s.data = str;
-  trans.setTransferData("text/unicode", s);
+  trans.setTransferData("text/plain", s);
   let inputEvent = null;
   window.addEventListener("input", aEvent => { inputEvent = aEvent; }, {once: true});
   getEditor().pasteTransferable(trans);

editor/spellchecker/tests/test_bug596333.html

@@ -49,7 +49,7 @@ function paste(str) {
   trans.init(getLoadContext());
   var s = Cc["@mozilla.org/supports-string;1"].createInstance(Ci.nsISupportsString);
   s.data = str;
-  trans.setTransferData("text/unicode", s);
+  trans.setTransferData("text/plain", s);
 
   let beforeInputEvent = null;
   let inputEvent = null;

gfx/tests/browser/browser_native_font_cache_macos.js

@@ -68,7 +68,7 @@ add_task(async () => {
             dump("********************\n");
             resolve("");
           },
-          "text/unicode",
+          "text/plain",
           REPORT_TIMEOUT_MS
         );
       });

mobile/android/actors/SelectionActionDelegateChild.jsm

@@ -72,7 +72,7 @@ class SelectionActionDelegateChild extends GeckoViewActorChild {
       predicate: e =>
         e.selectionEditable &&
         Services.clipboard.hasDataMatchingFlavors(
-          ["text/unicode"],
+          ["text/plain"],
           Ci.nsIClipboard.kGlobalClipboard
         ),
       perform: _ => this._performPaste(),

mobile/android/geckoview/src/main/java/org/mozilla/gecko/Clipboard.java

@@ -15,7 +15,7 @@ import org.mozilla.gecko.annotation.WrapForJNI;
 
 public final class Clipboard {
   private static final String HTML_MIME = "text/html";
-  private static final String UNICODE_MIME = "text/unicode";
+  private static final String PLAINTEXT_MIME = "text/plain";
   private static final String LOGTAG = "GeckoClipboard";
 
   private Clipboard() {}
@@ -27,14 +27,14 @@ public final class Clipboard {
    * @return a plain text string of clipboard data.
    */
   public static String getText(final Context context) {
-    return getData(context, UNICODE_MIME);
+    return getData(context, PLAINTEXT_MIME);
   }
 
   /**
    * Get the data on the primary clip on clipboard
    *
    * @param context application context
-   * @param mimeType the mime type we want. This supports text/html and text/unicode only. If other
+   * @param mimeType the mime type we want. This supports text/html and text/plain only. If other
    *     type, we do nothing.
    * @return a string into clipboard.
    */
@@ -57,7 +57,7 @@ public final class Clipboard {
         }
         return data.toString();
       }
-      if (UNICODE_MIME.equals(mimeType)) {
+      if (PLAINTEXT_MIME.equals(mimeType)) {
         try {
           return clip.getItemAt(0).coerceToText(context).toString();
         } catch (final SecurityException e) {
@@ -130,7 +130,7 @@ public final class Clipboard {
   @WrapForJNI(calledFrom = "gecko")
   public static boolean hasData(final Context context, final String mimeType) {
     if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.P) {
-      if (HTML_MIME.equals(mimeType) || UNICODE_MIME.equals(mimeType)) {
+      if (HTML_MIME.equals(mimeType) || PLAINTEXT_MIME.equals(mimeType)) {
         return !TextUtils.isEmpty(getData(context, mimeType));
       }
       return false;
@@ -155,7 +155,7 @@ public final class Clipboard {
       return description.hasMimeType(ClipDescription.MIMETYPE_TEXT_HTML);
     }
 
-    if (UNICODE_MIME.equals(mimeType)) {
+    if (PLAINTEXT_MIME.equals(mimeType)) {
       // We cannot check content in data at this time to avoid toast message.
       return description.hasMimeType(ClipDescription.MIMETYPE_TEXT_HTML)
           || description.hasMimeType(ClipDescription.MIMETYPE_TEXT_PLAIN);

testing/mochitest/tests/SimpleTest/SimpleTest.js

@@ -1063,7 +1063,7 @@ const kTextHtmlSuffixClipboardDataWindows =
  * Polls the clipboard waiting for the expected value. A known value different than
  * the expected value is put on the clipboard first (and also polled for) so we
  * can be sure the value we get isn't just the expected value because it was already
- * on the clipboard. This only uses the global clipboard and only for text/unicode
+ * on the clipboard. This only uses the global clipboard and only for text/plain
  * values.
  *
  * @param {String|Function} aExpectedStringOrValidatorFn
@@ -1087,7 +1087,7 @@ const kTextHtmlSuffixClipboardDataWindows =
  * @param {Function} aFailureFn
  *        A function called if the expected value isn't found on the clipboard
  *        within 5s. It can also be called if the known value can't be found.
- * @param {String} [aFlavor="text/unicode"]
+ * @param {String} [aFlavor="text/plain"]
  *        The flavor to look for.
  * @param {Number} [aTimeout=5000]
  *        The timeout (in milliseconds) to wait for a clipboard change.
@@ -1131,7 +1131,7 @@ SimpleTest.promiseClipboardChange = async function(
   aExpectFailure,
   aDontInitializeClipboardIfExpectFailure
 ) {
-  let requestedFlavor = aFlavor || "text/unicode";
+  let requestedFlavor = aFlavor || "text/plain";
 
   // The known value we put on the clipboard before running aSetupFn
   let initialVal = "waitForClipboard-known-value-" + Math.random();
@@ -1223,7 +1223,7 @@ SimpleTest.promiseClipboardChange = async function(
       function(aData) {
         return aData == preExpectedVal;
       },
-      "text/unicode",
+      "text/plain",
       false
     );
 

toolkit/components/aboutmemory/tests/test_aboutmemory3.xhtml

@@ -99,7 +99,7 @@
         // differences.
         synthesizeKey("A", {accelKey: true});
         synthesizeKey("C", {accelKey: true});
-        let actual = SpecialPowers.getClipboardData("text/unicode");
+        let actual = SpecialPowers.getClipboardData("text/plain");
         actual = actual.replace(/\(pid \d+\)/g, "(pid NNN)");
 
         if (actual.trim() === aExpected.trim()) {

toolkit/components/aboutmemory/tests/test_aboutmemory4.xhtml

@@ -50,7 +50,7 @@
         // differences.
         synthesizeKey("A", {accelKey: true});
         synthesizeKey("C", {accelKey: true});
-        let actual = SpecialPowers.getClipboardData("text/unicode");
+        let actual = SpecialPowers.getClipboardData("text/plain");
         actual = actual.replace(/\(pid \d+\)/, "(pid NNN)");
 
         if (actual.trim() === aExpected.trim()) {

toolkit/components/aboutmemory/tests/test_aboutmemory5.xhtml

@@ -105,7 +105,7 @@
         // differences.
         synthesizeKey("A", {accelKey: true});
         synthesizeKey("C", {accelKey: true});
-        let actual = SpecialPowers.getClipboardData("text/unicode");
+        let actual = SpecialPowers.getClipboardData("text/plain");
 
         // If we have more than 1000 chars, we've probably successfully
         // copy+pasted.

toolkit/components/extensions/test/mochitest/test_ext_async_clipboard.html

@@ -179,7 +179,7 @@ add_task(async function test_contentscript_clipboard_permission_writetext() {
   await extension.startup();
   let win = window.open("https://example.com/tests/toolkit/components/extensions/test/mochitest/file_sample.html");
   await extension.awaitMessage("ready");
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   is(actual, "HI", "right string copied by write");
   win.close();
   await extension.unload();
@@ -219,7 +219,7 @@ add_task(async function test_contentscript_clipboard_permission_readtext() {
   };
   await SimpleTest.promiseClipboardChange("HI", () => {
     SpecialPowers.clipboardCopyString("HI");
-  }, "text/unicode");
+  }, "text/plain");
   let extension = ExtensionTestUtils.loadExtension(extensionData);
   await extension.startup();
   let win = window.open("https://example.com/tests/toolkit/components/extensions/test/mochitest/file_sample.html");
@@ -262,7 +262,7 @@ add_task(async function test_contentscript_clipboard_permission_write() {
   await extension.startup();
   let win = window.open("https://example.com/tests/toolkit/components/extensions/test/mochitest/file_sample.html");
   await extension.awaitMessage("ready");
-  const actual = SpecialPowers.getClipboardData("text/unicode");
+  const actual = SpecialPowers.getClipboardData("text/plain");
   is(actual, "HI", "right string copied by write");
   win.close();
   await extension.unload();
@@ -303,7 +303,7 @@ add_task(async function test_contentscript_clipboard_permission_read() {
   };
   await SimpleTest.promiseClipboardChange("HELLO", () => {
     SpecialPowers.clipboardCopyString("HELLO");
-  }, "text/unicode");
+  }, "text/plain");
   let extension = ExtensionTestUtils.loadExtension(extensionData);
   await extension.startup();
   let win = window.open("https://example.com/tests/toolkit/components/extensions/test/mochitest/file_sample.html");

toolkit/components/pdfjs/test/browser_pdfjs_download_button.js

@@ -101,7 +101,7 @@ add_task(async function test_downloading_pdf_nonprivate_window() {
 
       SpecialPowers.clipboardCopyString("");
       DownloadsCommon.copyDownloadLink(dl);
-      const copiedUrl = SpecialPowers.getClipboardData("text/unicode");
+      const copiedUrl = SpecialPowers.getClipboardData("text/plain");
       is(copiedUrl, pdfUrl, "The copied url must be the original one");
 
       is(

toolkit/components/places/PlacesUtils.sys.mjs

@@ -430,7 +430,7 @@ export var PlacesUtils = {
   // Place entries formatted as HTML anchors
   TYPE_HTML: "text/html",
   // Place entries as raw URL text
-  TYPE_UNICODE: "text/unicode",
+  TYPE_PLAINTEXT: "text/plain",
   // Used to track the action that populated the clipboard.
   TYPE_X_MOZ_PLACE_ACTION: "text/x-moz-place-action",
 
@@ -1102,7 +1102,7 @@ export var PlacesUtils = {
       }
     }
 
-    // Otherwise, we wrap as TYPE_UNICODE.
+    // Otherwise, we wrap as TYPE_PLAINTEXT.
     return gatherDataFromNode(aNode, gatherDataText);
   },
 
@@ -1158,11 +1158,11 @@ export var PlacesUtils = {
         }
         break;
       }
-      case this.TYPE_UNICODE: {
+      case this.TYPE_PLAINTEXT: {
         let parts = blob.split("\n");
         for (let i = 0; i < parts.length; i++) {
           let uriString = parts[i];
-          // text/uri-list is converted to TYPE_UNICODE but it could contain
+          // text/uri-list is converted to TYPE_PLAINTEXT but it could contain
           // comments line prepended by #, we should skip them, as well as
           // empty uris.
           if (uriString.substr(0, 1) == "\x23" || uriString == "") {

toolkit/components/places/tests/unit/test_PlacesUtils_unwrapNodes_place.js

@@ -20,9 +20,9 @@ add_task(function() {
       PlacesUtils.TYPE_X_MOZ_URL,
     ],
     // Single url.
-    ["place:type=0&sort=1:", PlacesUtils.TYPE_UNICODE],
+    ["place:type=0&sort=1:", PlacesUtils.TYPE_PLAINTEXT],
     // Multiple urls.
-    ["place:type=0&sort=1:\nplace:type=0&sort=1", PlacesUtils.TYPE_UNICODE],
+    ["place:type=0&sort=1:\nplace:type=0&sort=1", PlacesUtils.TYPE_PLAINTEXT],
   ];
   for (let [blob, type] of tests) {
     Assert.deepEqual(

toolkit/components/reader/test/browser_drag_url_readerMode.js

@@ -45,7 +45,7 @@ add_task(async function test_readerModeURLDrag() {
       urlBarContainer.click();
       urlbar.dispatchEvent(urlEvent);
 
-      let newUrl = urlEvent.dataTransfer.getData("text/unicode");
+      let newUrl = urlEvent.dataTransfer.getData("text/plain");
       ok(!newUrl.includes("about:reader"), "URL does not contain about:reader");
 
       Assert.equal(newUrl, oldUrl, "URL is the same");

toolkit/content/aboutSupport.js

@@ -1377,8 +1377,8 @@ function copyRawDataToClipboard(button) {
         "@mozilla.org/widget/transferable;1"
       ].createInstance(Ci.nsITransferable);
       transferable.init(getLoadContext());
-      transferable.addDataFlavor("text/unicode");
+      transferable.addDataFlavor("text/plain");
-      transferable.setTransferData("text/unicode", str);
+      transferable.setTransferData("text/plain", str);
       Services.clipboard.setData(
         transferable,
         null,
@@ -1422,9 +1422,9 @@ async function copyContentsToClipboard() {
   transferable.setTransferData("text/html", ssHtml);
 
   // Add the plain text flavor.
-  transferable.addDataFlavor("text/unicode");
+  transferable.addDataFlavor("text/plain");
   ssText.data = dataText;
-  transferable.setTransferData("text/unicode", ssText);
+  transferable.setTransferData("text/plain", ssText);
 
   // Store the data into the clipboard.
   Services.clipboard.setData(

toolkit/modules/Finder.sys.mjs

@@ -821,12 +821,12 @@ export function GetClipboardSearchString(aLoadContext) {
       Ci.nsITransferable
     );
     trans.init(aLoadContext);
-    trans.addDataFlavor("text/unicode");
+    trans.addDataFlavor("text/plain");
 
     Services.clipboard.getData(trans, Ci.nsIClipboard.kFindClipboard);
 
     let data = {};
-    trans.getTransferData("text/unicode", data);
+    trans.getTransferData("text/plain", data);
     if (data.value) {
       data = data.value.QueryInterface(Ci.nsISupportsString);
       searchString = data.toString();

toolkit/mozapps/extensions/internal/AddonRepository.jsm

@@ -105,7 +105,7 @@ function convertHTMLToPlainText(html) {
   input.data = html.replace(/\n/g, "<br>");
 
   var output = {};
-  converter.convert("text/html", input, "text/unicode", output);
+  converter.convert("text/html", input, "text/plain", output);
 
   if (output.value instanceof Ci.nsISupportsString) {
     return output.value.data.replace(/\r\n/g, "\n");

widget/android/nsClipboard.cpp

@@ -15,7 +15,7 @@ using namespace mozilla;
 NS_IMPL_ISUPPORTS(nsClipboard, nsIClipboard)
 
 /* The Android clipboard only supports text and doesn't support mime types
- * so we assume all clipboard data is text/unicode for now. Documentation
+ * so we assume all clipboard data is text/plain for now. Documentation
  * indicates that support for other data types is planned for future
  * releases.
  */
@@ -38,10 +38,10 @@ nsClipboard::SetData(nsITransferable* aTransferable, nsIClipboardOwner* anOwner,
   nsAutoString text;
 
   for (auto& flavorStr : flavors) {
-    if (flavorStr.EqualsLiteral(kUnicodeMime)) {
+    if (flavorStr.EqualsLiteral(kTextMime)) {
       nsCOMPtr<nsISupports> item;
       nsresult rv =
-          aTransferable->GetTransferData(kUnicodeMime, getter_AddRefs(item));
+          aTransferable->GetTransferData(kTextMime, getter_AddRefs(item));
       if (NS_WARN_IF(NS_FAILED(rv))) {
         continue;
       }
@@ -89,7 +89,7 @@ nsClipboard::GetData(nsITransferable* aTransferable, int32_t aWhichClipboard) {
   aTransferable->FlavorsTransferableCanImport(flavors);
 
   for (auto& flavorStr : flavors) {
-    if (flavorStr.EqualsLiteral(kUnicodeMime) ||
+    if (flavorStr.EqualsLiteral(kTextMime) ||
         flavorStr.EqualsLiteral(kHTMLMime)) {
       auto text = java::Clipboard::GetData(
           java::GeckoAppShell::GetApplicationContext(), flavorStr);

widget/cocoa/nsChildView.mm

@@ -4513,7 +4513,7 @@ static CFTypeRefPtr<CFURLRef> GetPasteLocation(NSPasteboard* aPasteboard) {
   if (NS_FAILED(rv)) return NO;
   trans->Init(nullptr);
 
-  trans->AddDataFlavor(kUnicodeMime);
+  trans->AddDataFlavor(kTextMime);
   trans->AddDataFlavor(kHTMLMime);
 
   rv = nsClipboard::TransferableFromPasteboard(trans, pboard);

widget/cocoa/nsClipboard.mm

@@ -146,7 +146,9 @@ nsresult nsClipboard::TransferableFromPasteboard(nsITransferable* aTransferable,
       }
 
       NSData* stringData;
-      if ([pboardType isEqualToString:[UTIHelper stringFromPboardType:NSPasteboardTypeRTF]]) {
+      bool isRTF =
+          [pboardType isEqualToString:[UTIHelper stringFromPboardType:NSPasteboardTypeRTF]];
+      if (isRTF) {
         stringData = [pString dataUsingEncoding:NSASCIIStringEncoding];
       } else {
         stringData = [pString dataUsingEncoding:NSUnicodeStringEncoding];
@@ -160,7 +162,7 @@ nsresult nsClipboard::TransferableFromPasteboard(nsITransferable* aTransferable,
 
       // The DOM only wants LF, so convert from MacOS line endings to DOM line endings.
       int32_t signedDataLength = dataLength;
-      nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(flavorStr, &clipboardDataPtr,
+      nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(isRTF, &clipboardDataPtr,
                                                          &signedDataLength);
       dataLength = signedDataLength;
 
@@ -700,7 +702,7 @@ NSDictionary* nsClipboard::PasteboardDictFromTransferable(nsITransferable* aTran
 }
 
 bool nsClipboard::IsStringType(const nsCString& aMIMEType, NSString** aPboardType) {
-  if (aMIMEType.EqualsLiteral(kUnicodeMime)) {
+  if (aMIMEType.EqualsLiteral(kTextMime)) {
     *aPboardType = [UTIHelper stringFromPboardType:NSPasteboardTypeString];
     return true;
   } else if (aMIMEType.EqualsLiteral(kRTFMime)) {

widget/cocoa/nsCocoaUtils.mm

@@ -1693,7 +1693,7 @@ void nsCocoaUtils::SetTransferDataForTypeFromPasteboardItem(nsITransferable* aTr
   }
 
   NSString* pString = nil;
-  if (aFlavor.EqualsLiteral(kUnicodeMime)) {
+  if (aFlavor.EqualsLiteral(kTextMime)) {
     pString = nsCocoaUtils::GetStringForTypeFromPasteboardItem(
         aItem, [UTIHelper stringFromPboardType:NSPasteboardTypeString]);
   } else if (aFlavor.EqualsLiteral(kHTMLMime)) {
@@ -1720,7 +1720,8 @@ void nsCocoaUtils::SetTransferDataForTypeFromPasteboardItem(nsITransferable* aTr
   }
   if (pString) {
     NSData* stringData;
-    if (aFlavor.EqualsLiteral(kRTFMime)) {
+    bool isRTF = aFlavor.EqualsLiteral(kRTFMime);
+    if (isRTF) {
       stringData = [pString dataUsingEncoding:NSASCIIStringEncoding];
     } else {
       stringData = [pString dataUsingEncoding:NSUnicodeStringEncoding];
@@ -1734,8 +1735,7 @@ void nsCocoaUtils::SetTransferDataForTypeFromPasteboardItem(nsITransferable* aTr
 
     // The DOM only wants LF, so convert from MacOS line endings to DOM line endings.
     int32_t signedDataLength = dataLength;
-    nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(aFlavor, &clipboardDataPtr,
+    nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(isRTF, &clipboardDataPtr, &signedDataLength);
-                                                       &signedDataLength);
     dataLength = signedDataLength;
 
     // skip BOM (Byte Order Mark to distinguish little or big endian)

widget/cocoa/nsDragService.mm

@@ -348,7 +348,7 @@ nsDragService::IsDataFlavorSupported(const char* aDataFlavor, bool* _retval) {
   if (dataFlavor.EqualsLiteral(kFileMime)) {
     type = [UTIHelper stringFromPboardType:(NSString*)kUTTypeFileURL];
     allowFileURL = true;
-  } else if (dataFlavor.EqualsLiteral(kUnicodeMime)) {
+  } else if (dataFlavor.EqualsLiteral(kTextMime)) {
     type = [UTIHelper stringFromPboardType:NSPasteboardTypeString];
   } else if (dataFlavor.EqualsLiteral(kHTMLMime)) {
     type = [UTIHelper stringFromPboardType:NSPasteboardTypeHTML];

widget/gtk/nsClipboard.cpp

@@ -282,8 +282,8 @@ nsClipboard::SetData(nsITransferable* aTransferable, nsIClipboardOwner* aOwner,
     nsCString& flavorStr = flavors[i];
     LOGCLIP("    processing target %s\n", flavorStr.get());
 
-    // Special case text/unicode since we can handle all of the string types.
+    // Special case text/plain since we can handle all of the string types.
-    if (flavorStr.EqualsLiteral(kUnicodeMime)) {
+    if (flavorStr.EqualsLiteral(kTextMime)) {
       LOGCLIP("    adding TEXT targets\n");
       gtk_target_list_add_text_targets(list, 0);
       continue;
@@ -473,7 +473,7 @@ static bool TransferableSetHTML(nsITransferable* aTransferable,
                                 Span<const char> aData) {
   nsLiteralCString mimeType(kHTMLMime);
 
-  // Convert text/html into our unicode format
+  // Convert text/html into our text format
   nsAutoCString charset;
   if (!GetHTMLCharset(aData, charset)) {
     // Fall back to utf-8 in case html/data is missing kHTMLMarkupPrefix.
@@ -577,27 +577,27 @@ nsClipboard::GetData(nsITransferable* aTransferable, int32_t aWhichClipboard) {
       return NS_OK;
     }
 
-    // Special case text/unicode since we can convert any
+    // Special case text/plain since we can convert any
-    // string into text/unicode
+    // string into text/plain
-    if (flavorStr.EqualsLiteral(kUnicodeMime)) {
+    if (flavorStr.EqualsLiteral(kTextMime)) {
-      LOGCLIP("    Getting unicode %s MIME clipboard data\n", flavorStr.get());
+      LOGCLIP("    Getting text %s MIME clipboard data\n", flavorStr.get());
 
       auto clipboardData = mContext->GetClipboardText(aWhichClipboard);
       if (!clipboardData) {
-        LOGCLIP("    failed to get unicode data\n");
+        LOGCLIP("    failed to get text data\n");
-        // If the type was text/unicode and we couldn't get
+        // If the type was text/plain and we couldn't get
         // text off the clipboard, run the next loop
         // iteration.
         continue;
       }
 
-      // Convert utf-8 into our unicode format.
+      // Convert utf-8 into our text format.
       NS_ConvertUTF8toUTF16 ucs2string(clipboardData.get());
       SetTransferableData(aTransferable, flavorStr,
                           (const char*)ucs2string.BeginReading(),
                           ucs2string.Length() * 2);
 
-      LOGCLIP("    got unicode data, length %zd\n", ucs2string.Length());
+      LOGCLIP("    got text data, length %zd\n", ucs2string.Length());
       return NS_OK;
     }
 
@@ -706,14 +706,14 @@ static RefPtr<GenericPromise> AsyncGetTextImpl(nsITransferable* aTransferable,
 
         // Convert utf-8 into our unicode format.
         NS_ConvertUTF8toUTF16 utf16string(aText, dataLength);
-        nsLiteralCString flavor(kUnicodeMime);
+        nsLiteralCString flavor(kTextMime);
         SetTransferableData(ref->mTransferable, flavor,
                             (const char*)utf16string.BeginReading(),
                             utf16string.Length() * 2);
         LOGCLIP("  text is set, length = %d", (int)dataLength);
         ref->mDataPromise->Resolve(true, __func__);
       },
-      new DataPromiseHandler(aTransferable, dataPromise, kUnicodeMime));
+      new DataPromiseHandler(aTransferable, dataPromise, kTextMime));
 
   return dataPromise;
 }
@@ -812,9 +812,9 @@ static RefPtr<GenericPromise> AsyncGetDataFlavor(nsITransferable* aTransferable,
     return AsyncGetDataImpl(aTransferable, aWhichClipboard, aFlavorStr.get(),
                             DATATYPE_IMAGE);
   }
-  // Special case text/unicode since we can convert any
+  // Special case text/plain since we can convert any
-  // string into text/unicode
+  // string into text/plain
-  if (aFlavorStr.EqualsLiteral(kUnicodeMime)) {
+  if (aFlavorStr.EqualsLiteral(kTextMime)) {
     LOGCLIP("  Getting unicode clipboard data");
     return AsyncGetTextImpl(aTransferable, aWhichClipboard);
   }
@@ -984,12 +984,12 @@ nsClipboard::HasDataMatchingFlavors(const nsTArray<nsCString>& aFlavorList,
   // Walk through the provided types and try to match it to a
   // provided type.
   for (auto& flavor : aFlavorList) {
-    // We special case text/unicode here.
+    // We special case text/plain here.
-    if (flavor.EqualsLiteral(kUnicodeMime) &&
+    if (flavor.EqualsLiteral(kTextMime) &&
         gtk_targets_include_text(targets.AsSpan().data(),
                                  targets.AsSpan().Length())) {
       *_retval = true;
-      LOGCLIP("    has kUnicodeMime\n");
+      LOGCLIP("    has kTextMime\n");
       return NS_OK;
     }
     for (const auto& target : targets.AsSpan()) {
@@ -1041,11 +1041,10 @@ RefPtr<DataFlavorsPromise> nsClipboard::AsyncHasDataMatchingFlavors(
         if (targetsNum) {
           for (auto& flavor : handler->mAcceptedFlavorList) {
             LOGCLIP("  looking for %s", flavor.get());
-            // We can convert any text to unicode.
+            if (flavor.EqualsLiteral(kTextMime) &&
-            if (flavor.EqualsLiteral(kUnicodeMime) &&
                 gtk_targets_include_text(targets, targetsNum)) {
               results.AppendElement(flavor);
-              LOGCLIP("    has kUnicodeMime\n");
+              LOGCLIP("    has kTextMime\n");
               continue;
             }
             for (int i = 0; i < targetsNum; i++) {
@@ -1085,7 +1084,7 @@ void nsClipboard::SelectionGetEvent(GtkClipboard* aClipboard,
                                     GtkSelectionData* aSelectionData) {
   // Someone has asked us to hand them something.  The first thing
   // that we want to do is see if that something includes text.  If
-  // it does, try to give it text/unicode after converting it to
+  // it does, try to give it text/plain after converting it to
   // utf-8.
 
   int32_t whichClipboard;
@@ -1119,13 +1118,13 @@ void nsClipboard::SelectionGetEvent(GtkClipboard* aClipboard,
 
   // Check to see if the selection data is some text type.
   if (gtk_targets_include_text(&selectionTarget, 1)) {
-    LOGCLIP("  providing text/unicode data\n");
+    LOGCLIP("  providing text/plain data\n");
     // Try to convert our internal type into a text string.  Get
     // the transferable for this clipboard and try to get the
-    // text/unicode type for it.
+    // text/plain type for it.
-    rv = trans->GetTransferData("text/unicode", getter_AddRefs(item));
+    rv = trans->GetTransferData("text/plain", getter_AddRefs(item));
     if (NS_FAILED(rv) || !item) {
-      LOGCLIP("  GetTransferData() failed to get text/unicode!\n");
+      LOGCLIP("  GetTransferData() failed to get text/plain!\n");
       return;
     }
 

widget/gtk/nsDragService.cpp

@@ -797,7 +797,13 @@ nsDragService::GetData(nsITransferable* aTransferable, uint32_t aItemIndex) {
   // format. SetTransferData() implicitly handles conversions.
   for (uint32_t i = 0; i < flavors.Length(); ++i) {
     nsCString& flavorStr = flavors[i];
-    GdkAtom gdkFlavor = gdk_atom_intern(flavorStr.get(), FALSE);
+
+    GdkAtom gdkFlavor;
+    if (flavorStr.EqualsLiteral(kTextMime)) {
+      gdkFlavor = gdk_atom_intern(gTextPlainUTF8Type, FALSE);
+    } else {
+      gdkFlavor = gdk_atom_intern(flavorStr.get(), FALSE);
+    }
     LOGDRAGSERVICE("  we're getting data %s (gdk flavor %p)\n", flavorStr.get(),
                    gdkFlavor);
     bool dataFound = false;
@@ -854,46 +860,15 @@ nsDragService::GetData(nsITransferable* aTransferable, uint32_t aItemIndex) {
         }
       }
 
-      // if we are looking for text/unicode and we fail to find it
+      // If we are looking for text/plain, try again with non utf-8 text.
-      // on the clipboard first, try again with text/plain. If that
+      if (flavorStr.EqualsLiteral(kTextMime)) {
-      // is present, convert it to unicode.
+        LOGDRAGSERVICE("  conversion %s => %s", kTextMime, kTextMime);
-      if (flavorStr.EqualsLiteral(kUnicodeMime)) {
+        gdkFlavor = gdk_atom_intern(kTextMime, FALSE);
-        LOGDRAGSERVICE("  conversion %s => %s", kUnicodeMime,
-                       gTextPlainUTF8Type);
-        gdkFlavor = gdk_atom_intern(gTextPlainUTF8Type, FALSE);
         GetTargetDragData(gdkFlavor, dragFlavors);
         if (mTargetDragData) {
-          const char* castedText = reinterpret_cast<char*>(mTargetDragData);
+          dataFound = true;
-          char16_t* convertedText = nullptr;
+        }  // if plain text flavor present
-          NS_ConvertUTF8toUTF16 ucs2string(castedText, mTargetDragDataLen);
+      }    // if looking for text/plain
-          convertedText = ToNewUnicode(ucs2string, mozilla::fallible);
-          if (convertedText) {
-            // out with the old, in with the new
-            g_free(mTargetDragData);
-            mTargetDragData = convertedText;
-            mTargetDragDataLen = ucs2string.Length() * 2;
-            dataFound = true;
-          }  // if plain text data on clipboard
-        } else {
-          LOGDRAGSERVICE("  conversion %s => %s", kUnicodeMime, kTextMime);
-          gdkFlavor = gdk_atom_intern(kTextMime, FALSE);
-          GetTargetDragData(gdkFlavor, dragFlavors);
-          if (mTargetDragData) {
-            const char* castedText = reinterpret_cast<char*>(mTargetDragData);
-            char16_t* convertedText = nullptr;
-            uint32_t convertedTextLen = 0;
-            UTF8ToNewUTF16(castedText, mTargetDragDataLen, &convertedText,
-                           &convertedTextLen);
-            if (convertedText) {
-              // out with the old, in with the new
-              g_free(mTargetDragData);
-              mTargetDragData = convertedText;
-              mTargetDragDataLen = convertedTextLen * 2;
-              dataFound = true;
-            }  // if plain text data on clipboard
-          }    // if plain text flavor present
-        }      // if plain text charset=utf-8 flavor present
-      }        // if looking for text/unicode
 
       // if we are looking for text/x-moz-url and we failed to find
       // it on the clipboard, try again with text/uri-list, and then
@@ -945,6 +920,18 @@ nsDragService::GetData(nsITransferable* aTransferable, uint32_t aItemIndex) {
       LOGDRAGSERVICE("  actual data found %s\n",
                      GUniquePtr<gchar>(gdk_atom_name(gdkFlavor)).get());
 
+      if (flavorStr.EqualsLiteral(kTextMime)) {
+        // The text is in UTF-8, so convert the text into UTF-16
+        const char* text = static_cast<char*>(mTargetDragData);
+        NS_ConvertUTF8toUTF16 ucs2string(text, mTargetDragDataLen);
+        char16_t* convertedText = ToNewUnicode(ucs2string, mozilla::fallible);
+        if (convertedText) {
+          g_free(mTargetDragData);
+          mTargetDragData = convertedText;
+          mTargetDragDataLen = ucs2string.Length() * 2;
+        }
+      }
+
       if (flavorStr.EqualsLiteral(kJPEGImageMime) ||
           flavorStr.EqualsLiteral(kJPGImageMime) ||
           flavorStr.EqualsLiteral(kPNGImageMime) ||
@@ -963,7 +950,7 @@ nsDragService::GetData(nsITransferable* aTransferable, uint32_t aItemIndex) {
         // the DOM only wants LF, so convert from MacOS line endings
         // to DOM line endings.
         nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(
-            flavorStr, &mTargetDragData,
+            flavorStr.EqualsLiteral(kRTFMime), &mTargetDragData,
             reinterpret_cast<int*>(&mTargetDragDataLen));
       }
 
@@ -1062,11 +1049,6 @@ nsDragService::IsDataFlavorSupported(const char* aDataFlavor, bool* _retval) {
              (strcmp(aDataFlavor, kURLMime) == 0)) {
       *_retval = true;
     }
-    // check for auto text/plain -> text/unicode mapping
-    else if (strcmp(name.get(), kTextMime) == 0 &&
-             (strcmp(aDataFlavor, kUnicodeMime) == 0)) {
-      *_retval = true;
-    }
 
     if (*_retval) {
       LOGDRAGSERVICE("  supported, with converting %s => %s", name.get(),
@@ -1374,13 +1356,9 @@ GtkTargetList* nsDragService::GetSourceList(void) {
         if (flavorStr.EqualsLiteral(kFileMime)) {
           TargetArrayAddTarget(targetArray, gTextUriListType);
         }
-        // Check to see if this is text/unicode.
+        // Check to see if this is text/plain.
-        // If it is, add text/plain
+        else if (flavorStr.EqualsLiteral(kTextMime)) {
-        // since we automatically support text/plain
-        // if we support text/unicode.
-        else if (flavorStr.EqualsLiteral(kUnicodeMime)) {
           TargetArrayAddTarget(targetArray, gTextPlainUTF8Type);
-          TargetArrayAddTarget(targetArray, kTextMime);
         }
         // Check to see if this is the x-moz-url type.
         // If it is, add _NETSCAPE_URL
@@ -2051,7 +2029,7 @@ void nsDragService::SourceDataGet(GtkWidget* aWidget, GdkDragContext* aContext,
 
   if (mimeFlavor.EqualsLiteral(kTextMime) ||
       mimeFlavor.EqualsLiteral(gTextPlainUTF8Type)) {
-    SourceDataGetText(item, nsDependentCString(kUnicodeMime),
+    SourceDataGetText(item, nsDependentCString(kTextMime),
                       /* aNeedToDoConversionToPlainText */ true,
                       aSelectionData);
     // no fallback for text mime types

widget/headless/HeadlessClipboard.cpp

@@ -29,8 +29,7 @@ HeadlessClipboard::SetData(nsITransferable* aTransferable,
 
   // Only support plain text for now.
   nsCOMPtr<nsISupports> clip;
-  nsresult rv =
+  nsresult rv = aTransferable->GetTransferData(kTextMime, getter_AddRefs(clip));
-      aTransferable->GetTransferData(kUnicodeMime, getter_AddRefs(clip));
   if (NS_FAILED(rv)) {
     return rv;
   }
@@ -60,7 +59,7 @@ HeadlessClipboard::GetData(nsITransferable* aTransferable,
     return rv;
   }
   nsCOMPtr<nsISupports> genericDataWrapper = do_QueryInterface(dataWrapper);
-  rv = aTransferable->SetTransferData(kUnicodeMime, genericDataWrapper);
+  rv = aTransferable->SetTransferData(kTextMime, genericDataWrapper);
   if (NS_WARN_IF(NS_FAILED(rv))) {
     return rv;
   }
@@ -86,7 +85,7 @@ HeadlessClipboard::HasDataMatchingFlavors(
   }
   // Retrieve the union of all aHasType in aFlavorList
   for (auto& flavor : aFlavorList) {
-    if (flavor.EqualsLiteral(kUnicodeMime) && mClipboard->HasText()) {
+    if (flavor.EqualsLiteral(kTextMime) && mClipboard->HasText()) {
       *aHasType = true;
       break;
     }

widget/headless/tests/test_headless_clipboard.js

@@ -10,13 +10,13 @@ function getString(clipboard) {
     Ci.nsITransferable
   );
   trans.init(null);
-  trans.addDataFlavor("text/unicode");
+  trans.addDataFlavor("text/plain");
 
   clipboard.getData(trans, Ci.nsIClipboard.kGlobalClipboard);
 
   try {
     var data = {};
-    trans.getTransferData("text/unicode", data);
+    trans.getTransferData("text/plain", data);
 
     if (data) {
       data = data.value.QueryInterface(Ci.nsISupportsString);

widget/nsClipboardHelper.cpp

@@ -73,7 +73,7 @@ nsClipboardHelper::CopyStringToClipboard(const nsAString& aString,
   }
 
   // Add the text data flavor to the transferable
-  rv = trans->AddDataFlavor(kUnicodeMime);
+  rv = trans->AddDataFlavor(kTextMime);
   NS_ENSURE_SUCCESS(rv, rv);
 
   // get wStrings to hold clip data
@@ -93,7 +93,7 @@ nsClipboardHelper::CopyStringToClipboard(const nsAString& aString,
   NS_ENSURE_TRUE(genericData, NS_ERROR_FAILURE);
 
   // set the transfer data
-  rv = trans->SetTransferData(kUnicodeMime, genericData);
+  rv = trans->SetTransferData(kTextMime, genericData);
   NS_ENSURE_SUCCESS(rv, rv);
 
   // put the transferable on the clipboard

widget/nsHTMLFormatConverter.cpp

@@ -46,7 +46,7 @@ nsHTMLFormatConverter::GetInputDataFlavors(nsTArray<nsCString>& aFlavors) {
 NS_IMETHODIMP
 nsHTMLFormatConverter::GetOutputDataFlavors(nsTArray<nsCString>& aFlavors) {
   aFlavors.AppendElement(nsLiteralCString(kHTMLMime));
-  aFlavors.AppendElement(nsLiteralCString(kUnicodeMime));
+  aFlavors.AppendElement(nsLiteralCString(kTextMime));
   return NS_OK;
 }
 
@@ -63,10 +63,11 @@ nsHTMLFormatConverter::CanConvert(const char* aFromDataFlavor,
 
   *_retval = false;
   if (!nsCRT::strcmp(aFromDataFlavor, kHTMLMime)) {
-    if (!nsCRT::strcmp(aToDataFlavor, kHTMLMime))
+    if (!nsCRT::strcmp(aToDataFlavor, kHTMLMime)) {
       *_retval = true;
-    else if (!nsCRT::strcmp(aToDataFlavor, kUnicodeMime))
+    } else if (!nsCRT::strcmp(aToDataFlavor, kTextMime)) {
       *_retval = true;
+    }
 #if NOT_NOW
     // pinkerton
     // no one uses this flavor right now, so it's just slowing things down. If
@@ -120,7 +121,7 @@ nsHTMLFormatConverter::Convert(const char* aFromDataFlavor,
     dataWrapper0->GetData(dataStr);  // COPY #1
     // note: conversion to text/plain is done inside the clipboard. we do not
     // need to worry about it here.
-    if (toFlavor.Equals(kHTMLMime) || toFlavor.Equals(kUnicodeMime)) {
+    if (toFlavor.Equals(kHTMLMime) || toFlavor.Equals(kTextMime)) {
       nsresult res;
       if (toFlavor.Equals(kHTMLMime)) {
         int32_t dataLen = dataStr.Length() * 2;

widget/nsITransferable.idl

@@ -23,7 +23,6 @@ interface nsIPrincipal;
 // by the entire app.
 #define kTextMime                   "text/plain"
 #define kRTFMime                    "text/rtf"
-#define kUnicodeMime                "text/unicode"
 #define kMozTextInternal            "text/x-moz-text-internal"  // text data which isn't suppoed to be parsed by other apps.
 #define kHTMLMime                   "text/html"
 #define kAOLMailMime                "AOLMAIL"

widget/nsPrimitiveHelpers.cpp

@@ -43,8 +43,7 @@ void nsPrimitiveHelpers ::CreatePrimitiveForData(const nsACString& aFlavor,
                                                  nsISupports** aPrimitive) {
   if (!aPrimitive) return;
 
-  if (aFlavor.EqualsLiteral(kTextMime) ||
+  if (aFlavor.EqualsLiteral(kNativeHTMLMime) ||
-      aFlavor.EqualsLiteral(kNativeHTMLMime) ||
       aFlavor.EqualsLiteral(kRTFMime) ||
       aFlavor.EqualsLiteral(kCustomTypesMime)) {
     nsCOMPtr<nsISupportsCString> primitive =
@@ -97,8 +96,7 @@ void nsPrimitiveHelpers ::CreatePrimitiveForCFHTML(const void* aDataBuff,
   void* utf8 = moz_xmalloc(*aDataLen);
   memcpy(utf8, aDataBuff, *aDataLen);
   int32_t signedLen = static_cast<int32_t>(*aDataLen);
-  nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(
+  nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(true, &utf8, &signedLen);
-      nsDependentCString(kTextMime), &utf8, &signedLen);
   *aDataLen = signedLen;
 
   nsAutoString str(
@@ -125,8 +123,7 @@ void nsPrimitiveHelpers::CreateDataFromPrimitive(const nsACString& aFlavor,
   *aDataBuff = nullptr;
   *aDataLen = 0;
 
-  if (aFlavor.EqualsLiteral(kTextMime) ||
+  if (aFlavor.EqualsLiteral(kCustomTypesMime)) {
-      aFlavor.EqualsLiteral(kCustomTypesMime)) {
     nsCOMPtr<nsISupportsCString> plainText(do_QueryInterface(aPrimitive));
     if (plainText) {
       nsAutoCString data;
@@ -156,13 +153,14 @@ void nsPrimitiveHelpers::CreateDataFromPrimitive(const nsACString& aFlavor,
 // NOTE: this assumes that it can use 'free' to dispose of the old buffer.
 //
 nsresult nsLinebreakHelpers ::ConvertPlatformToDOMLinebreaks(
-    const nsACString& inFlavor, void** ioData, int32_t* ioLengthInBytes) {
+    bool aIsSingleByteChars, void** ioData, int32_t* ioLengthInBytes) {
   NS_ASSERTION(ioData && *ioData && ioLengthInBytes, "Bad Params");
   if (!(ioData && *ioData && ioLengthInBytes)) return NS_ERROR_INVALID_ARG;
 
   nsresult retVal = NS_OK;
 
-  if (inFlavor.EqualsLiteral(kTextMime) || inFlavor.EqualsLiteral(kRTFMime)) {
+  // RTF and CF_HTML on Windows are transfered as single-byte characters.
+  if (aIsSingleByteChars) {
     char* buffAsChars = reinterpret_cast<char*>(*ioData);
     char* oldBuffer = buffAsChars;
     retVal = nsLinebreakConverter::ConvertLineBreaksInSitu(
@@ -174,8 +172,6 @@ nsresult nsLinebreakHelpers ::ConvertPlatformToDOMLinebreaks(
         free(oldBuffer);
       *ioData = buffAsChars;
     }
-  } else if (inFlavor.EqualsLiteral("image/jpeg")) {
-    // I'd assume we don't want to do anything for binary data....
   } else {
     char16_t* buffAsUnichar = reinterpret_cast<char16_t*>(*ioData);
     char16_t* oldBuffer = buffAsUnichar;

widget/nsPrimitiveHelpers.h

@@ -45,7 +45,7 @@ class nsLinebreakHelpers {
   // taken care of internally, see the note below).
   //
   // NOTE: this assumes that it can use 'free' to dispose of the old buffer.
-  static nsresult ConvertPlatformToDOMLinebreaks(const nsACString& inFlavor,
+  static nsresult ConvertPlatformToDOMLinebreaks(bool aIsSingleByteChars,
                                                  void** ioData,
                                                  int32_t* ioLengthInBytes);
 

widget/tests/test_bug1123480.xhtml

@@ -111,8 +111,8 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=1123480
       var Suppstr = nsSupportsString();
       Suppstr.data = Ipsum;
       Transfer.init(Loadctx);
-      Transfer.addDataFlavor("text/unicode");
+      Transfer.addDataFlavor("text/plain");
-      Transfer.setTransferData("text/unicode", Suppstr);
+      Transfer.setTransferData("text/plain", Suppstr);
 
       // Enabled private browsing mode should not cache any selection to disk; disabled should
       if (private) {
@@ -132,7 +132,7 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=1123480
       // Sanitize the environment.
       Suppstr = nsSupportsString();
       Suppstr.data = SHORT_STRING_NO_CACHE;
-      Transfer.setTransferData("text/unicode", Suppstr);
+      Transfer.setTransferData("text/plain", Suppstr);
       await new Promise(resolve => setTimeout(resolve, 0));
       is(getClipboardCacheFDCount(), initialFdCount, "should drop the cache file, if any.");
 

widget/tests/test_bug673301.xhtml

@@ -21,13 +21,13 @@ var transferable = Cc['@mozilla.org/widget/transferable;1']
                              .createInstance(Ci.nsITransferable);
 transferable.init(getLoadContext());
 
-transferable.addDataFlavor("text/unicode");
+transferable.addDataFlavor("text/plain");
-transferable.setTransferData("text/unicode", document);
+transferable.setTransferData("text/plain", document);
 
 Services.clipboard.setData(transferable, null, Ci.nsIClipboard.kGlobalClipboard);
 
-transferable.setTransferData("text/unicode", null);
+transferable.setTransferData("text/plain", null);
 
-SimpleTest.ok(true, "Didn't crash setting non-text data for text/unicode type");
+SimpleTest.ok(true, "Didn't crash setting non-text data for text/plain type");
 </script>
 </window>

widget/tests/test_clipboard.xhtml

@@ -31,11 +31,11 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=948065
     let trans = Cc['@mozilla.org/widget/transferable;1']
                 .createInstance(Ci.nsITransferable);
     trans.init(getLoadContext());
-    trans.addDataFlavor("text/unicode");
+    trans.addDataFlavor("text/plain");
     clipboard.getData(trans, Ci.nsIClipboard.kGlobalClipboard);
     let str = {};
     try {
-      trans.getTransferData('text/unicode', str);
+      trans.getTransferData('text/plain', str);
     } catch (e) {
       str = '';
     }

widget/tests/test_clipboard_cache.xhtml

@@ -58,17 +58,17 @@ clipboardTypes.forEach(function(type) {
     add_task(function test_clipboard_hasDataMatchingFlavors() {
       info(`Test write data to clipboard type ${type}`);
 
-      // Write text/unicode data to main clipboard.
+      // Write text/plain data to main clipboard.
-      writeStringToClipboard(GenerateRandomString(), "text/unicode", clipboard.kGlobalClipboard);
+      writeStringToClipboard(GenerateRandomString(), "text/plain", clipboard.kGlobalClipboard);
-      ok(clipboard.hasDataMatchingFlavors(["text/unicode"], clipboard.kGlobalClipboard),
+      ok(clipboard.hasDataMatchingFlavors(["text/plain"], clipboard.kGlobalClipboard),
-         "Should have text/unicode flavor");
+         "Should have text/plain flavor");
       ok(!clipboard.hasDataMatchingFlavors(["text/html"], clipboard.kGlobalClipboard),
          "Should not have text/html flavor");
 
       // Write text/html data to other clipboard.
       writeStringToClipboard(GenerateRandomString(), "text/html", type);
-      ok(clipboard.hasDataMatchingFlavors(["text/unicode"], clipboard.kGlobalClipboard),
+      ok(clipboard.hasDataMatchingFlavors(["text/plain"], clipboard.kGlobalClipboard),
-         "Should have text/unicode flavor");
+         "Should have text/plain flavor");
       ok(!clipboard.hasDataMatchingFlavors(["text/html"], clipboard.kGlobalClipboard),
          "Should not have text/html flavor");
 

widget/tests/test_transferable_overflow.xhtml

@@ -24,12 +24,12 @@
   function assignTextToTransferable(transferable, string) {
     var Suppstr = nsSupportsString();
     Suppstr.data = string;
-    transferable.setTransferData("text/unicode", Suppstr);
+    transferable.setTransferData("text/plain", Suppstr);
   }
 
   function checkTransferableText(transferable, expectedString, description) {
     var data = {};
-    transferable.getTransferData("text/unicode", data);
+    transferable.getTransferData("text/plain", data);
     var actualValue = data.value.QueryInterface(Ci.nsISupportsString).data;
     // Use ok + shortenString instead of is(...) to avoid dumping millions of characters in the output.
     ok(actualValue === expectedString, description + ": text should match. " +
@@ -89,7 +89,7 @@
     var Loadctx = PrivateBrowsingUtils.privacyContextFromWindow(win);
     var Transfer = nsTransferable();
     Transfer.init(Loadctx);
-    Transfer.addDataFlavor("text/unicode");
+    Transfer.addDataFlavor("text/plain");
     var initialFdCount = isFDCountingSupported() ? getClipboardCacheFDCount() : -1;
 
     assignTextToTransferable(Transfer, BIG_STRING);
@@ -117,7 +117,7 @@
 
     var Transfer2 = nsTransferable();
     Transfer2.init(Loadctx);
-    Transfer2.addDataFlavor("text/unicode");
+    Transfer2.addDataFlavor("text/plain");
 
     // Iniitalize with a small string, so we can see that mData -> mCacheFD works.
     assignTextToTransferable(Transfer2, SMALL_STRING);

widget/windows/nsClipboard.cpp

@@ -99,8 +99,6 @@ UINT nsClipboard::GetFormat(const char* aMimeStr, bool aMapHTMLMime) {
   UINT format;
 
   if (strcmp(aMimeStr, kTextMime) == 0) {
-    format = CF_TEXT;
-  } else if (strcmp(aMimeStr, kUnicodeMime) == 0) {
     format = CF_UNICODETEXT;
   } else if (strcmp(aMimeStr, kRTFMime) == 0) {
     format = ::RegisterClipboardFormat(L"Rich Text Format");
@@ -210,9 +208,9 @@ nsresult nsClipboard::SetupNativeDataObject(
     // Do various things internal to the implementation, like map one
     // flavor to another or add additional flavors based on what's required
     // for the win32 impl.
-    if (flavorStr.EqualsLiteral(kUnicodeMime)) {
+    if (flavorStr.EqualsLiteral(kTextMime)) {
-      // if we find text/unicode, also advertise text/plain (which we will
+      // if we find text/plain, also add CF_TEXT, but we can add it for
-      // convert on our own in nsDataObj::GetText().
+      // text/plain as well.
       FORMATETC textFE;
       SET_FORMATETC(textFE, CF_TEXT, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL);
       dObj->AddDataFlavor(kTextMime, &textFE);
@@ -888,7 +886,7 @@ nsresult nsClipboard::GetDataFromDataObject(IDataObject* aDataObject,
     // when directly asking for the flavor. Let's try digging around in other
     // flavors to help satisfy our craving for data.
     if (!dataFound) {
-      if (flavorStr.EqualsLiteral(kUnicodeMime)) {
+      if (flavorStr.EqualsLiteral(kTextMime)) {
         dataFound =
             FindUnicodeFromPlainText(aDataObject, anIndex, &data, &dataLen);
       } else if (flavorStr.EqualsLiteral(kURLMime)) {
@@ -954,14 +952,15 @@ nsresult nsClipboard::GetDataFromDataObject(IDataObject* aDataObject,
       } else {
         // Treat custom types as a string of bytes.
         if (!flavorStr.EqualsLiteral(kCustomTypesMime)) {
+          bool isRTF = flavorStr.EqualsLiteral(kRTFMime);
           // we probably have some form of text. The DOM only wants LF, so
           // convert from Win32 line endings to DOM line endings.
           int32_t signedLen = static_cast<int32_t>(dataLen);
-          nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(flavorStr, &data,
+          nsLinebreakHelpers::ConvertPlatformToDOMLinebreaks(isRTF, &data,
                                                              &signedLen);
           dataLen = signedLen;
 
-          if (flavorStr.EqualsLiteral(kRTFMime)) {
+          if (isRTF) {
             // RTF on Windows is known to sometimes deliver an extra null byte.
             if (dataLen > 0 && static_cast<char*>(data)[dataLen - 1] == '\0') {
               dataLen--;
@@ -1049,20 +1048,21 @@ bool nsClipboard ::FindPlatformHTML(IDataObject* inDataObject, UINT inIndex,
 //
 // FindUnicodeFromPlainText
 //
-// we are looking for text/unicode and we failed to find it on the clipboard
+// Looks for CF_TEXT on the clipboard and converts it into an UTF-16 string
-// first, try again with text/plain. If that is present, convert it to unicode.
+// if present. Returns this string in outData, and its length in outDataLen.
+// XXXndeakin Windows converts between CF_UNICODE and CF_TEXT automatically
+// so it doesn't seem like this is actually needed.
 //
 bool nsClipboard ::FindUnicodeFromPlainText(IDataObject* inDataObject,
                                             UINT inIndex, void** outData,
                                             uint32_t* outDataLen) {
   MOZ_LOG(gWin32ClipboardLog, LogLevel::Debug, ("%s", __FUNCTION__));
 
-  // we are looking for text/unicode and we failed to find it on the clipboard
+  // We are looking for text/plain and we failed to find it on the clipboard
-  // first, try again with text/plain. If that is present, convert it to
+  // first, so try again with CF_TEXT. If that is present, convert it to
   // unicode.
-  nsresult rv =
+  nsresult rv = GetNativeDataOffClipboard(inDataObject, inIndex, CF_TEXT,
-      GetNativeDataOffClipboard(inDataObject, inIndex, GetFormat(kTextMime),
+                                          nullptr, outData, outDataLen);
-                                nullptr, outData, outDataLen);
   if (NS_FAILED(rv) || !*outData) {
     return false;
   }
@@ -1303,30 +1303,10 @@ NS_IMETHODIMP nsClipboard::HasDataMatchingFlavors(
   }
 
   for (auto& flavor : aFlavorList) {
-#ifdef DEBUG
-    if (flavor.EqualsLiteral(kTextMime)) {
-      NS_WARNING(
-          "DO NOT USE THE text/plain DATA FLAVOR ANY MORE. USE text/unicode "
-          "INSTEAD");
-    }
-#endif
-
     UINT format = GetFormat(flavor.get());
     if (IsClipboardFormatAvailable(format)) {
       *_retval = true;
       break;
-    } else {
-      // We haven't found the exact flavor the client asked for, but maybe we
-      // can still find it from something else that's on the clipboard...
-      if (flavor.EqualsLiteral(kUnicodeMime)) {
-        // client asked for unicode and it wasn't present, check if we have
-        // CF_TEXT. We'll handle the actual data substitution in the data
-        // object.
-        if (IsClipboardFormatAvailable(GetFormat(kTextMime))) {
-          *_retval = true;
-          break;
-        }
-      }
     }
   }
 

widget/windows/nsDataObj.cpp

@@ -1428,26 +1428,19 @@ HRESULT nsDataObj::GetText(const nsACString& aDataFlavor, FORMATETC& aFE,
                            STGMEDIUM& aSTG) {
   void* data = nullptr;
 
-  // if someone asks for text/plain, look up text/unicode instead in the
+  const nsPromiseFlatCString& flavorStr = PromiseFlatCString(aDataFlavor);
-  // transferable.
-  const char* flavorStr;
-  const nsPromiseFlatCString& flat = PromiseFlatCString(aDataFlavor);
-  if (aDataFlavor.EqualsLiteral("text/plain"))
-    flavorStr = kUnicodeMime;
-  else
-    flavorStr = flat.get();
 
   // NOTE: CreateDataFromPrimitive creates new memory, that needs to be deleted
   nsCOMPtr<nsISupports> genericDataWrapper;
   nsresult rv = mTransferable->GetTransferData(
-      flavorStr, getter_AddRefs(genericDataWrapper));
+      flavorStr.get(), getter_AddRefs(genericDataWrapper));
   if (NS_FAILED(rv) || !genericDataWrapper) {
     return E_FAIL;
   }
 
   uint32_t len;
-  nsPrimitiveHelpers::CreateDataFromPrimitive(nsDependentCString(flavorStr),
+  nsPrimitiveHelpers::CreateDataFromPrimitive(
-                                              genericDataWrapper, &data, &len);
+      nsDependentCString(flavorStr.get()), genericDataWrapper, &data, &len);
   if (!data) return E_FAIL;
 
   HGLOBAL hGlobalMemory = nullptr;

widget/windows/nsDragService.cpp

@@ -451,13 +451,6 @@ NS_IMETHODIMP
 nsDragService::IsDataFlavorSupported(const char* aDataFlavor, bool* _retval) {
   if (!aDataFlavor || !mDataObject || !_retval) return NS_ERROR_FAILURE;
 
-#ifdef DEBUG
-  if (strcmp(aDataFlavor, kTextMime) == 0)
-    NS_WARNING(
-        "DO NOT USE THE text/plain DATA FLAVOR ANY MORE. USE text/unicode "
-        "INSTEAD");
-#endif
-
   *_retval = false;
 
   FORMATETC fe;
@@ -494,12 +487,12 @@ nsDragService::IsDataFlavorSupported(const char* aDataFlavor, bool* _retval) {
       // We haven't found the exact flavor the client asked for, but
       // maybe we can still find it from something else that's on the
       // clipboard
-      if (strcmp(aDataFlavor, kUnicodeMime) == 0) {
+      if (strcmp(aDataFlavor, kTextMime) == 0) {
-        // client asked for unicode and it wasn't present, check if we
+        // If unicode wasn't there, it might exist as CF_TEXT, client asked
+        // for unicode and it wasn't present, check if we
         // have CF_TEXT.  We'll handle the actual data substitution in
         // the data object.
-        format = nsClipboard::GetFormat(kTextMime);
+        SET_FORMATETC(fe, CF_TEXT, 0, DVASPECT_CONTENT, -1,
-        SET_FORMATETC(fe, format, 0, DVASPECT_CONTENT, -1,
                       TYMED_HGLOBAL | TYMED_FILE | TYMED_GDI);
         if (mDataObject->QueryGetData(&fe) == S_OK)
           *_retval = true;  // found it!