diff --git a/browser/base/content/tabbrowser.js b/browser/base/content/tabbrowser.js
index f1d264d84fec8..ca0367a34ca23 100644
--- a/browser/base/content/tabbrowser.js
+++ b/browser/base/content/tabbrowser.js
@@ -5641,14 +5641,14 @@
 
         case ShortcutUtils.NEXT_TAB:
           if (AppConstants.platform == "macosx") {
-            this.tabContainer.advanceSelectedTab(1, true);
-            aEvent.preventDefault();
+//            this.tabContainer.advanceSelectedTab(1, true);
+//            aEvent.preventDefault();
           }
           break;
         case ShortcutUtils.PREVIOUS_TAB:
           if (AppConstants.platform == "macosx") {
-            this.tabContainer.advanceSelectedTab(-1, true);
-            aEvent.preventDefault();
+//            this.tabContainer.advanceSelectedTab(-1, true);
+//            aEvent.preventDefault();
           }
           break;
       }
diff --git a/toolkit/content/widgets/tabbox.js b/toolkit/content/widgets/tabbox.js
index 997e8413f2a22..178c1dee73632 100644
--- a/toolkit/content/widgets/tabbox.js
+++ b/toolkit/content/widgets/tabbox.js
@@ -134,20 +134,20 @@
             true
           );
           if (this.tabs && this.handleCtrlTab) {
-            this.tabs.advanceSelectedTab(event.shiftKey ? -1 : 1, true);
-            event.preventDefault();
+//            this.tabs.advanceSelectedTab(event.shiftKey ? -1 : 1, true);
+//            event.preventDefault();
           }
           break;
         case ShortcutUtils.PREVIOUS_TAB:
           if (this.tabs) {
-            this.tabs.advanceSelectedTab(-1, true);
-            event.preventDefault();
+//            this.tabs.advanceSelectedTab(-1, true);
+//            event.preventDefault();
           }
           break;
         case ShortcutUtils.NEXT_TAB:
           if (this.tabs) {
-            this.tabs.advanceSelectedTab(1, true);
-            event.preventDefault();
+  //          this.tabs.advanceSelectedTab(1, true);
+//            event.preventDefault();
           }
           break;
       }
diff --git a/dom/events/EventStateManager.cpp b/dom/events/EventStateManager.cpp
index 01c7ed0125d69..33c915f3e3cf5 100644
--- a/dom/events/EventStateManager.cpp
+++ b/dom/events/EventStateManager.cpp
@@ -3379,6 +3379,12 @@ void EventStateManager::PostHandleKeyboardEvent(
         EnsureDocument(presContext);
         nsFocusManager* fm = nsFocusManager::GetFocusManager();
         if (fm && mDocument) {
+
+          // We don't care about tab movement, it's handled by Sidebery
+          if (aKeyboardEvent->IsControl() && aKeyboardEvent->mKeyCode == NS_VK_TAB) {
+            return;
+          }
+
           // Shift focus forward or back depending on shift key
           bool isDocMove = aKeyboardEvent->IsControl() ||
                            aKeyboardEvent->mKeyCode == NS_VK_F6;
diff --git a/browser/base/content/browser-sets.inc b/browser/base/content/browser-sets.inc
index d08984b796330..3b32785b3b3cc 100644
--- a/browser/base/content/browser-sets.inc
+++ b/browser/base/content/browser-sets.inc
@@ -32,7 +32,7 @@
     <command id="cmd_printPreviewToggle" oncommand="PrintUtils.togglePrintPreview(gBrowser.selectedBrowser.browsingContext);"/>
     <command id="cmd_file_importFromAnotherBrowser" oncommand="MigrationUtils.showMigrationWizard(window, { entrypoint: MigrationUtils.MIGRATION_ENTRYPOINTS.FILE_MENU });"/>
     <command id="cmd_help_importFromAnotherBrowser" oncommand="MigrationUtils.showMigrationWizard(window, { entrypoint: MigrationUtils.MIGRATION_ENTRYPOINTS.HELP_MENU });"/>
-    <command id="cmd_close" oncommand="BrowserCloseTabOrWindow(event);"/>
+#    <command id="cmd_close" oncommand="BrowserCloseTabOrWindow(event);"/>
     <command id="cmd_closeWindow" oncommand="BrowserTryToCloseWindow(event)"/>
     <command id="cmd_toggleMute" oncommand="gBrowser.toggleMuteAudioOnMultiSelectedTabs(gBrowser.selectedTab)"/>
     <command id="cmd_CustomizeToolbars" oncommand="gCustomizeMode.enter()"/>
@@ -75,8 +75,8 @@
     <command id="Browser:ReloadSkipCache" oncommand="BrowserCommands.reloadSkipCache()" disabled="true">
       <observes element="Browser:Reload" attribute="disabled"/>
     </command>
-    <command id="Browser:NextTab" oncommand="gBrowser.tabContainer.advanceSelectedTab(1, true);"/>
-    <command id="Browser:PrevTab" oncommand="gBrowser.tabContainer.advanceSelectedTab(-1, true);"/>
+#    <command id="Browser:NextTab" oncommand="gBrowser.tabContainer.advanceSelectedTab(1, true);"/>
+#    <command id="Browser:PrevTab" oncommand="gBrowser.tabContainer.advanceSelectedTab(-1, true);"/>
     <command id="Browser:ShowAllTabs" oncommand="gTabsPanel.showAllTabsPanel();"/>
     <command id="cmd_fullZoomReduce"  oncommand="FullZoom.reduce()"/>
     <command id="cmd_fullZoomEnlarge" oncommand="FullZoom.enlarge()"/>
@@ -167,7 +167,7 @@
          modifiers="accel"
 #endif
          command="Tools:Downloads"/>
-    <key id="key_openAddons" data-l10n-id="addons-shortcut" command="Tools:Addons" modifiers="accel,shift"/>
+#    <key id="key_openAddons" data-l10n-id="addons-shortcut" command="Tools:Addons" modifiers="accel,shift"/>
     <key id="openFileKb" data-l10n-id="file-open-shortcut" command="Browser:OpenFile"  modifiers="accel"/>
     <key id="key_savePage" data-l10n-id="save-page-shortcut" command="Browser:SavePage" modifiers="accel"/>
     <key id="printKb" data-l10n-id="print-shortcut" command="cmd_print"  modifiers="accel"/>
@@ -179,13 +179,8 @@
          modifiers="accel"
          internal="true"/>
     <key id="key_redo"
-#ifdef XP_UNIX
-         data-l10n-id="text-action-undo-shortcut"
-         modifiers="accel,shift"
-#else
          data-l10n-id="text-action-redo-shortcut"
          modifiers="accel"
-#endif
          internal="true"/>
     <key id="key_cut"
          data-l10n-id="text-action-cut-shortcut"
@@ -223,7 +218,7 @@
     <key id="key_enterFullScreen" keycode="VK_F11" command="View:FullScreen"/>
     <key id="key_exitFullScreen" keycode="VK_F11" command="View:FullScreen" reserved="true" disabled="true"/>
 #else
-    <key id="showAllHistoryKb" data-l10n-id="history-show-all-shortcut-mac" command="Browser:ShowAllHistory" modifiers="accel"/>
+    <key id="showAllHistoryKb" data-l10n-id="history-show-all-shortcut-mac" command="Browser:ShowAllHistory" modifiers="accel,shift"/>
     <key id="key_enterFullScreen" data-l10n-id="full-screen-shortcut" command="View:FullScreen" modifiers="accel,control"/>
     <key id="key_enterFullScreen_old" data-l10n-id="full-screen-shortcut" command="View:FullScreen" modifiers="accel,shift"/>
     <key id="key_enterFullScreen_compat" keycode="VK_F11" command="View:FullScreen"/>
@@ -341,15 +336,15 @@
 #define NUM_SELECT_TAB_MODIFIER accel
 #endif
 
-#expand    <key id="key_selectTab1" oncommand="gBrowser.selectTabAtIndex(0, event);" key="1" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectTab2" oncommand="gBrowser.selectTabAtIndex(1, event);" key="2" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectTab3" oncommand="gBrowser.selectTabAtIndex(2, event);" key="3" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectTab4" oncommand="gBrowser.selectTabAtIndex(3, event);" key="4" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectTab5" oncommand="gBrowser.selectTabAtIndex(4, event);" key="5" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectTab6" oncommand="gBrowser.selectTabAtIndex(5, event);" key="6" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectTab7" oncommand="gBrowser.selectTabAtIndex(6, event);" key="7" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectTab8" oncommand="gBrowser.selectTabAtIndex(7, event);" key="8" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
-#expand    <key id="key_selectLastTab" oncommand="gBrowser.selectTabAtIndex(-1, event);" key="9" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab1" oncommand="gBrowser.selectTabAtIndex(0, event);" key="1" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab2" oncommand="gBrowser.selectTabAtIndex(1, event);" key="2" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab3" oncommand="gBrowser.selectTabAtIndex(2, event);" key="3" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab4" oncommand="gBrowser.selectTabAtIndex(3, event);" key="4" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab5" oncommand="gBrowser.selectTabAtIndex(4, event);" key="5" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab6" oncommand="gBrowser.selectTabAtIndex(5, event);" key="6" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab7" oncommand="gBrowser.selectTabAtIndex(6, event);" key="7" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectTab8" oncommand="gBrowser.selectTabAtIndex(7, event);" key="8" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
+# #expand    <key id="key_selectLastTab" oncommand="gBrowser.selectTabAtIndex(-1, event);" key="9" modifiers="__NUM_SELECT_TAB_MODIFIER__"/>
 
     <key id="key_wrCaptureCmd"
 #ifdef XP_MACOSX
diff --git a/toolkit/content/editMenuKeys.inc.xhtml b/toolkit/content/editMenuKeys.inc.xhtml
index d4331b32dc770..9a501aa83755c 100644
--- a/toolkit/content/editMenuKeys.inc.xhtml
+++ b/toolkit/content/editMenuKeys.inc.xhtml
@@ -7,15 +7,7 @@
 
   <keyset id="editMenuKeys">
     <key id="key_undo" data-l10n-id="text-action-undo-shortcut" modifiers="accel" command="cmd_undo"/>
-    <key id="key_redo"
-#ifdef XP_UNIX
-    data-l10n-id="text-action-undo-shortcut"
-    modifiers="accel,shift"
-#else
-    data-l10n-id="text-action-redo-shortcut"
-    modifiers="accel"
-#endif
-    command="cmd_redo"/>
+    <key id="key_redo" data-l10n-id="text-action-redo-shortcut" modifiers="accel" command="cmd_redo"/>
     <key id="key_cut" data-l10n-id="text-action-cut-shortcut" modifiers="accel" command="cmd_cut"/>
     <key id="key_copy" data-l10n-id="text-action-copy-shortcut" modifiers="accel" command="cmd_copy"/>
     <key id="key_paste" data-l10n-id="text-action-paste-shortcut" modifiers="accel" command="cmd_paste"/>
diff --git a/dom/events/ShortcutKeyDefinitions.cpp b/dom/events/ShortcutKeyDefinitions.cpp
index 3f34f45240444..bdf404b1e90b0 100644
--- a/dom/events/ShortcutKeyDefinitions.cpp
+++ b/dom/events/ShortcutKeyDefinitions.cpp
@@ -176,7 +176,7 @@ ShortcutKeyData ShortcutKeys::sInputHandlers[] = {
     {u"keypress", nullptr, u"x", u"accel",       u"cmd_cut"},    // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"v", u"accel",       u"cmd_paste"},  // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"z", u"accel",       u"cmd_undo"},   // Win, macOS, Linux, Android, Emacs
-    {u"keypress", nullptr, u"z", u"accel,shift", u"cmd_redo"},   // Win, macOS, Linux, Android, Emacs
+    {u"keypress", nullptr, u"y", u"accel",       u"cmd_redo"},   // Win, macOS, Linux, Android, Emacs
 
     {u"keypress", nullptr, u"v", u"accel,shift",     u"cmd_paste"},  // Win, macOS, Linux, Android, Emacs
 // Mac uses Option+Shift+Command+V for Paste and Match Style
@@ -184,11 +184,6 @@ ShortcutKeyData ShortcutKeys::sInputHandlers[] = {
     {u"keypress", nullptr, u"v", u"accel,alt,shift", u"cmd_paste"},  // macOS
 #endif  // MOZ_WIDGET_COCOA
 
-#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK) ||\
-    defined(USE_EMACS_KEY_BINDINGS)
-    {u"keypress", nullptr, u"y", u"accel",       u"cmd_redo"},   // Win, Linux, Emacs
-#endif  // XP_WIN || MOZ_WIDGET_GTK || USE_EMACS_KEY_BINDINGS
-
 #if defined(XP_WIN) || defined(MOZ_WIDGET_COCOA) || defined(MOZ_WIDGET_GTK) ||\
     defined(MOZ_WIDGET_ANDROID)
     {u"keypress", nullptr, u"a", u"accel",       u"cmd_selectAll"},  // Win, macOS, Linux, Android
@@ -365,12 +360,7 @@ ShortcutKeyData ShortcutKeys::sTextAreaHandlers[] = {
     {u"keypress", nullptr, u"x", u"accel",       u"cmd_cut"},        // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"v", u"accel",       u"cmd_paste"},      // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"z", u"accel",       u"cmd_undo"},       // Win, macOS, Linux, Android, Emacs
-    {u"keypress", nullptr, u"z", u"accel,shift", u"cmd_redo"},       // Win, macOS, Linux, Android, Emacs
-
-#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK) ||\
-    defined(USE_EMACS_KEY_BINDINGS)
-    {u"keypress", nullptr, u"y", u"accel",       u"cmd_redo"},       // Win, Linux, Emacs
-#endif  // XP_WIN || MOZ_WIDGET_GTK || USE_EMACS_KEY_BINDINGS
+    {u"keypress", nullptr, u"y", u"accel",       u"cmd_redo"},       // Win, macOS, Linux, Android, Emacs
 
 #if defined(XP_WIN) || defined(MOZ_WIDGET_COCOA) || defined(MOZ_WIDGET_GTK) ||\
     defined(MOZ_WIDGET_ANDROID)
@@ -561,17 +551,13 @@ ShortcutKeyData ShortcutKeys::sBrowserHandlers[] = {
     {u"keypress", nullptr, u"v", u"accel",       u"cmd_paste"},             // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"v", u"accel,shift", u"cmd_pasteNoFormatting"}, // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"z", u"accel",       u"cmd_undo"},              // Win, macOS, Linux, Android, Emacs
-    {u"keypress", nullptr, u"z", u"accel,shift", u"cmd_redo"},              // Win, macOS, Linux, Android, Emacs
+    {u"keypress", nullptr, u"y", u"accel",       u"cmd_redo"},              // Win, macOS, Linux, Android, Emacs
 
 // Mac uses Option+Shift+Command+V for Paste and Match Style
 #if defined(MOZ_WIDGET_COCOA)
     {u"keypress", nullptr, u"v", u"accel,alt,shift", u"cmd_pasteNoFormatting"},  // macOS
 #endif  // MOZ_WIDGET_COCOA
 
-#if defined(XP_WIN)
-    {u"keypress", nullptr, u"y", u"accel",       u"cmd_redo"},       // Win
-#endif  // XP_WIN
-
     {u"keypress", nullptr, u"a", u"accel",       u"cmd_selectAll"},  // Win, macOS, Linux, Android, Emacs
 #if defined(USE_EMACS_KEY_BINDINGS)
     {u"keypress", nullptr, u"a", u"alt",         u"cmd_selectAll"},  // Emacs
@@ -730,18 +716,13 @@ ShortcutKeyData ShortcutKeys::sEditorHandlers[] = {
     {u"keypress", nullptr, u"v", u"accel",           u"cmd_paste"},              // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"v", u"accel,shift",     u"cmd_pasteNoFormatting"},  // Win, macOS, Linux, Android, Emacs
     {u"keypress", nullptr, u"z", u"accel",           u"cmd_undo"},               // Win, macOS, Linux, Android, Emacs
-    {u"keypress", nullptr, u"z", u"accel,shift",     u"cmd_redo"},               // Win, macOS, Linux, Android, Emacs
+    {u"keypress", nullptr, u"y", u"accel",           u"cmd_redo"},               // Win, macOS, Linux, Android, Emacs
 
 // Mac uses Option+Shift+Command+V for Paste and Match Style
 #if defined(MOZ_WIDGET_COCOA)
     {u"keypress", nullptr, u"v", u"accel,alt,shift", u"cmd_pasteNoFormatting"},  // macOS
 #endif  // MOZ_WIDGET_COCOA
 
-#if defined(XP_WIN) || defined(MOZ_WIDGET_GTK) ||\
-    defined(USE_EMACS_KEY_BINDINGS)
-    {u"keypress", nullptr, u"y", u"accel",           u"cmd_redo"},               // Emacs
-#endif  // XP_WIN || MOZ_WIDGET_GTK || USE_EMACS_KEY_BINDINGS
-
 #if defined(XP_WIN) || defined(MOZ_WIDGET_COCOA) || defined(MOZ_WIDGET_GTK) ||\
     defined(MOZ_WIDGET_ANDROID)
     {u"keypress", nullptr, u"a", u"accel",           u"cmd_selectAll"},          // Win, macOS, Linux, Android