ungoogled-chromium/patches/extra/ungoogled-chromium/add-flag-to-scroll-tabs.patch

--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -248,6 +248,16 @@ const FeatureEntry::Choice kShowAvatarBu
      "never"}
 };
 
+const FeatureEntry::Choice kScrollEventChangesTab[] = {
+    {flags_ui::kGenericExperimentChoiceDefault, "", ""},
+    {"Always",
+     "scroll-tabs",
+     "always"},
+    {"Never",
+     "scroll-tabs",
+     "never"}
+};
+
 const FeatureEntry::Choice kTouchEventFeatureDetectionChoices[] = {
     {flags_ui::kGenericExperimentChoiceDisabled, "", ""},
     {flags_ui::kGenericExperimentChoiceEnabled,
@@ -3601,6 +3611,11 @@ const FeatureEntry kFeatureEntries[] = {
      kOsAndroid, FEATURE_VALUE_TYPE(safe_browsing::kUseLocalBlacklistsV2)},
 #endif  // defined(OS_ANDROID)
 
+    {"scroll-tabs",
+     "Scroll switches tab",
+     "Switch to the left/right tab if the wheel-scroll happens over the tabstrip, or the empty space beside the tabstrip.", kOsDesktop,
+     MULTI_VALUE_TYPE(kScrollEventChangesTab)},
+
 #if defined(OS_CHROMEOS)
     {"enable-native-google-assistant",
      flag_descriptions::kEnableGoogleAssistantName,
--- a/chrome/browser/ui/views/frame/browser_root_view.cc
+++ b/chrome/browser/ui/views/frame/browser_root_view.cc
@@ -8,6 +8,7 @@
 #include <string>
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/metrics/user_metrics.h"
 #include "base/task/post_task.h"
 #include "chrome/browser/autocomplete/autocomplete_classifier_factory.h"
@@ -91,6 +92,18 @@ int GetDropEffect(const ui::DropTargetEv
   return ui::DragDropTypes::DRAG_MOVE;
 }
 
+bool ShouldScrollChangesTab() {
+  const std::string flag_value =
+    base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII("scroll-tabs");
+
+  if (flag_value == "always")
+    return true;
+  else if (flag_value == "never")
+    return false;
+
+  return browser_defaults::kScrollEventChangesTab;
+}
+
 }  // namespace
 
 BrowserRootView::DropInfo::DropInfo() = default;
@@ -105,7 +118,9 @@ const char BrowserRootView::kViewClassNa
 
 BrowserRootView::BrowserRootView(BrowserView* browser_view,
                                  views::Widget* widget)
-    : views::internal::RootView(widget), browser_view_(browser_view) {}
+    : views::internal::RootView(widget), browser_view_(browser_view) {
+  scroll_event_changes_tab_ = ShouldScrollChangesTab();
+}
 
 BrowserRootView::~BrowserRootView() = default;
 
@@ -238,7 +253,7 @@ const char* BrowserRootView::GetClassNam
 }
 
 bool BrowserRootView::OnMouseWheel(const ui::MouseWheelEvent& event) {
-  if (browser_defaults::kScrollEventChangesTab) {
+  if (scroll_event_changes_tab_) {
     // Switch to the left/right tab if the wheel-scroll happens over the
     // tabstrip, or the empty space beside the tabstrip.
     views::View* hit_view = GetEventHandlerForPoint(event.location());
--- a/chrome/browser/ui/views/frame/browser_root_view.h
+++ b/chrome/browser/ui/views/frame/browser_root_view.h
@@ -125,6 +125,8 @@ class BrowserRootView : public views::in
   int scroll_remainder_x_ = 0;
   int scroll_remainder_y_ = 0;
 
+  bool scroll_event_changes_tab_ = false;
+
   std::unique_ptr<DropInfo> drop_info_;
 
   base::WeakPtrFactory<BrowserRootView> weak_ptr_factory_{this};