From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Raymond Zhao <7199958+rzhao271@users.noreply.github.com>
Date: Wed, 17 Aug 2022 13:49:40 -0700
Subject: fix: Adjust caption-removing style call

There is a SetWindowLong call that removes WS_CAPTION for frameless
windows, but Electron uses WS_CAPTION even for frameless windows,
unless they are transparent.

Changing this call only affects frameless windows, and it fixes
a visual glitch where they showed a Windows 7 style frame
during startup.

The if statement was originally introduced by
https://codereview.chromium.org/9372053/, and it was there to fix
a visual glitch with the close button showing up during startup
or resizing, but Electron does not seem to run into that issue
for opaque frameless windows even with that block commented out.

diff --git a/ui/views/win/hwnd_message_handler.cc b/ui/views/win/hwnd_message_handler.cc
index 400278ab26a4e095fd837fcf84c952a1297b173d..55afa69870f27b877826ea8a442ab20a8b336d74 100644
--- a/ui/views/win/hwnd_message_handler.cc
+++ b/ui/views/win/hwnd_message_handler.cc
@@ -1731,7 +1731,23 @@ LRESULT HWNDMessageHandler::OnCreate(CREATESTRUCT* create_struct) {
   SendMessage(hwnd(), WM_CHANGEUISTATE, MAKELPARAM(UIS_CLEAR, UISF_HIDEFOCUS),
               0);
 
-  if (!delegate_->HasFrame()) {
+  LONG is_popup =
+      GetWindowLong(hwnd(), GWL_STYLE) & static_cast<LONG>(WS_POPUP);
+
+  // For transparent windows, Electron removes the WS_CAPTION style,
+  // so we continue to remove it here. If we didn't, an opaque rectangle
+  // would show up.
+  // For non-transparent windows, Electron keeps the WS_CAPTION style,
+  // so we don't remove it in that case. If we did, a Windows 7 frame
+  // would show up.
+  // We also need this block for frameless popup windows. When the user opens
+  // a dropdown in an Electron app, the internal popup menu from
+  // third_party/blink/renderer/core/html/forms/internal_popup_menu.h
+  // is rendered. That menu is actually an HTML page inside of a frameless popup window.
+  // A new popup window is created every time the user opens the dropdown,
+  // and this code path is run. The code block below runs SendFrameChanged,
+  // which gives the dropdown options the proper layout.
+  if (!delegate_->HasFrame() && (is_translucent_ || is_popup)) {
     SetWindowLong(hwnd(), GWL_STYLE,
                   GetWindowLong(hwnd(), GWL_STYLE) & ~WS_CAPTION);
     SendFrameChanged();
