fix: WCO occlusion of DevTools (#35209)

docs/api/web-contents.md

@@ -1568,6 +1568,8 @@ Opens the devtools.
 When `contents` is a `<webview>` tag, the `mode` would be `detach` by default,
 explicitly passing an empty `mode` can force using last used dock state.
 
+On Windows, if Windows Control Overlay is enabled, Devtools will be opened with `mode: 'detach'`.
+
 #### `contents.closeDevTools()`
 
 Closes the devtools.

shell/browser/api/electron_api_web_contents.cc

@@ -175,6 +175,7 @@
 
 #if BUILDFLAG(IS_WIN)
 #include "printing/backend/win_helper.h"
+#include "shell/browser/native_window_views.h"
 #endif
 #endif
 
@@ -2419,6 +2420,14 @@ void WebContents::OpenDevTools(gin::Arguments* args) {
     }
   }
 
+#if BUILDFLAG(IS_WIN)
+  auto* win = static_cast<NativeWindowViews*>(owner_window());
+  // Force a detached state when WCO is enabled to match Chrome
+  // behavior and prevent occlusion of DevTools.
+  if (win && win->IsWindowControlsOverlayEnabled())
+    state = "detach";
+#endif
+
   DCHECK(inspectable_web_contents_);
   inspectable_web_contents_->SetDockState(state);
   inspectable_web_contents_->ShowDevTools(activate);