feat: expose vertical tabs preferences

patches/enable-vertical-tabs-exposure.patch

@@ -0,0 +1,25 @@
+Copyright 2026 The Trivalent Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software distributed under the License is
+distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and limitations under the License.
+---
+diff --git a/chrome/browser/ui/tabs/features.cc b/chrome/browser/ui/tabs/features.cc
+index faa16e19c8..11db930e93 100644
+--- a/chrome/browser/ui/tabs/features.cc
++++ b/chrome/browser/ui/tabs/features.cc
+@@ -15,7 +15,7 @@ BASE_FEATURE(kTabGroupHome, base::FEATURE_DISABLED_BY_DEFAULT);
+ BASE_FEATURE(kSessionRestoreShowThrobberOnVisible,
+              base::FEATURE_DISABLED_BY_DEFAULT);
+
+-BASE_FEATURE(kVerticalTabs, base::FEATURE_DISABLED_BY_DEFAULT);
++BASE_FEATURE(kVerticalTabs, base::FEATURE_ENABLED_BY_DEFAULT);
+
+ BASE_FEATURE(kVerticalTabsLaunch, base::FEATURE_DISABLED_BY_DEFAULT);
+ BASE_FEATURE_PARAM(bool,