fix: use native PiP windows on Wayland

Mark Electron Document Picture-in-Picture windows and teach Chromium Ozone to use the experimental xx-pip-v1 compositor role when available. This removes compositor decorations and gives supported Wayland compositors explicit PiP stacking semantics while retaining the xdg_toplevel fallback elsewhere.

Author: D3SOX

lib/browser/guest-window-manager.ts

@@ -46,9 +46,12 @@ export function openGuestWindow({
 }): void {
   const { url, frameName, features } = windowOpenArgs;
   const { options: parsedOptions } = parseFeatures(features);
-  const pictureInPictureOptions: BrowserWindowConstructorOptions =
+  const pictureInPictureOptions: BrowserWindowConstructorOptions & {
+    _isPictureInPicture?: boolean;
+  } =
     disposition === 'picture-in-picture'
       ? {
+          _isPictureInPicture: true,
           alwaysOnTop: true,
           autoHideMenuBar: true,
           frame: false,

patches/chromium/.patches

@@ -163,3 +163,4 @@ revert_remove_the_feature_flag_kdropinputeventswhilepaintholding.patch
 fix_disable_enable_resource_allowlist_generation_on_windows.patch
 fix_fall_back_to_an_unlocalized_touch_id_prompt_reason_when_the.patch
 revert_only_preload_swiftshader_in_gpu_sandbox_init_when_allowed.patch
+feat_support_native_picture-in-picture_on_wayland.patch