feat: add option to disable close button on tabs

(cherry picked from commit ff68d8fd9ff678e6cf7efb6d662728b223322ba4)

waterfox/browser/app/profile/00-general.js

@@ -32,6 +32,7 @@ pref("app.update.url.override", "", sticky); // Override URL for application upd
 // Defines browser behavior on startup and general UI settings.
 pref("browser.startup.page", 3); // 0=blank, 1=home, 2=last visited page, 3=resume previous session.
 pref("browser.privateTab.showNewTabButton", false); // Show new private tab button next to existing new tab buttons
+pref("browser.tabs.closeButtons", false); // Hide close button on tabs
 pref("browser.tabs.pinnedIconOnly", true); // Pinned tabs show only an icon, no text.
 pref("browser.tabs.warnOnClose", true); // Warn user when attempting to close multiple tabs.
 // Stores the state of toolbar customizations (e.g., button placements).

waterfox/browser/components/WaterfoxGlue.sys.mjs

@@ -90,6 +90,15 @@ export const WaterfoxGlue = {
         lazy.BrowserUtils.registerOrUnregisterSheet(uri, !isEnabled);
       }
     );
+    this.styleSheetChanges = lazy.PrefUtils.addObserver(
+      "browser.tabs.closeButtons",
+      () => {
+        // Pref being true actually means we need to unload the sheet, so invert.
+        const uri = "chrome://browser/skin/waterfox/general.css";
+        lazy.BrowserUtils.unregisterStylesheet(uri);
+        lazy.BrowserUtils.registerStylesheet(uri);
+      }
+    )
   },
 
   async getChromeManifest(manifest) {

waterfox/browser/themes/waterfox/general.css

@@ -181,3 +181,9 @@
 #preferences-body .main-content {
   overflow-x: hidden !important;
 }
+
+@supports -moz-bool-pref("browser.tabs.closeButtons") {
+  .tab-close-button {
+    display: none !important
+  }
+}