Bug 1674091 - Don't update the state of the Other Bookmarks shortcut folder if the personal-bookmarks item has been placed in the palette. r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D96764

browser/base/content/browser-places.js

@@ -2318,19 +2318,21 @@ var BookmarkingUI = {
   },
 
   async maybeShowOtherBookmarksFolder() {
+    // otherBookmarks may be null if personal-bookmarks is in the palette.
+    let otherBookmarks = document.getElementById("OtherBookmarks");
+
     // Only show the "Other Bookmarks" folder in the toolbar if pref is enabled.
-    if (!gBookmarksToolbar2h2020) {
+    if (!gBookmarksToolbar2h2020 || !otherBookmarks) {
       return;
     }
 
     let unfiledGuid = PlacesUtils.bookmarks.unfiledGuid;
     let numberOfBookmarks = PlacesUtils.getChildCountForFolder(unfiledGuid);
-    let otherBookmarks = document.getElementById("OtherBookmarks");
     let placement = CustomizableUI.getPlacementOfWidget("personal-bookmarks");
 
     if (
       numberOfBookmarks > 0 &&
-      placement.area == CustomizableUI.AREA_BOOKMARKS
+      placement?.area == CustomizableUI.AREA_BOOKMARKS
     ) {
       let otherBookmarksPopup = document.getElementById("OtherBookmarksPopup");
       let result = PlacesUtils.getFolderContents(unfiledGuid);

browser/components/places/tests/browser/browser_toolbar_other_bookmarks.js

@@ -219,6 +219,30 @@ add_task(async function testDeletingMenuItems() {
   await closeMenuPopup("#OtherBookmarksPopup");
 });
 
+add_task(async function no_errors_when_bookmarks_placed_in_palette() {
+  CustomizableUI.removeWidgetFromArea("personal-bookmarks");
+
+  let consoleErrors = 0;
+
+  let errorListener = {
+    observe(error) {
+      ok(false, error.message);
+      consoleErrors++;
+    },
+  };
+  Services.console.registerListener(errorListener);
+
+  let bookmarks = await PlacesUtils.bookmarks.insertTree({
+    guid: PlacesUtils.bookmarks.unfiledGuid,
+    children: bookmarksInfo,
+  });
+  is(consoleErrors, 0, "There should be no console errors");
+
+  Services.console.unregisterListener(errorListener);
+  await PlacesUtils.bookmarks.remove(bookmarks);
+  CustomizableUI.reset();
+});
+
 /**
  * Tests whether or not the "Other Bookmarks" folder is visible.
  */