Bug 1960668: Make Unified Search Button unavailable if the page was loaded as background r=tabbrowser-reviewers,daleharvey,dao

Differential Revision: https://phabricator.services.mozilla.com/D245714

browser/components/urlbar/UrlbarInput.sys.mjs

@@ -275,6 +275,7 @@ export class UrlbarInput {
     this.window.addEventListener("unload", this);
 
     this.window.gBrowser.tabContainer.addEventListener("TabSelect", this);
+    this.window.gBrowser.addTabsProgressListener(this);
 
     this.window.addEventListener("customizationstarting", this);
     this.window.addEventListener("aftercustomization", this);
@@ -666,6 +667,29 @@ export class UrlbarInput {
     return uri;
   }
 
+  /**
+   * Function for tabs progress listener.
+   *
+   * @param {nsIBrowser} browser
+   * @param {nsIWebProgress} webProgress
+   *   The nsIWebProgress instance that fired the notification.
+   * @param {nsIRequest} request
+   *   The associated nsIRequest.  This may be null in some cases.
+   * @param {nsIURI} location
+   *   The URI of the location that is being loaded.
+   */
+  onLocationChange(browser, webProgress, request, location) {
+    if (
+      webProgress.isTopLevel &&
+      browser != this.window.gBrowser.selectedBrowser &&
+      !this.window.isBlankPageURL(location.spec)
+    ) {
+      // If the page is loaded on background tab, make Unified Search Button
+      // unavailable when back to the tab.
+      this.getBrowserState(browser).isUnifiedSearchButtonAvailable = false;
+    }
+  }
+
   /**
    * Passes DOM events to the _on_<event type> methods.
    *

browser/components/urlbar/tests/browser/browser_searchModeSwitcher_dynamicUnifiedSearchButton.js

@@ -15,6 +15,41 @@ add_setup(async function setup() {
   });
 });
 
+add_task(async function test_button_visibility_by_loaded_on_background() {
+  info("Open valid page that loads slow");
+  let tab1 = await BrowserTestUtils.openNewForegroundTab({
+    gBrowser,
+    opening:
+      getRootDirectory(gTestPath).replace(
+        "chrome://mochitests/content",
+        "https://www.example.com"
+      ) + "slow-page.sjs",
+    waitForLoad: false,
+  });
+  await assertState(true, "invalid");
+
+  info("Open a new tab");
+  let tab2 = await BrowserTestUtils.openNewForegroundTab(gBrowser);
+  await assertState(true, "invalid");
+
+  info("Wait until loading the slow page on background");
+  // eslint-disable-next-line mozilla/no-arbitrary-setTimeout
+  await new Promise(r => setTimeout(r, 5000));
+  await TestUtils.waitForCondition(
+    () =>
+      !gURLBar.getBrowserState(tab1.linkedBrowser)
+        .isUnifiedSearchButtonAvailable
+  );
+
+  info("Select the previous tab");
+  gBrowser.selectedTab = tab1;
+  await assertState(false, "valid");
+
+  info("Clean up");
+  BrowserTestUtils.removeTab(tab2);
+  BrowserTestUtils.removeTab(tab1);
+});
+
 add_task(async function test_button_visibility_by_pageproxystate() {
   info("Open pageproxystate valid page");
   let tab = await BrowserTestUtils.openNewForegroundTab(