Fullscreen is treated as an Exclusive Fullscreen on Windows

[Lielay9]

Godot version

v4.1.beta3.official [ada712e]

System information

Godot v4.1.beta3 - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 4090 (NVIDIA; 31.0.15.3623) - AMD Ryzen 9 7950X 16-Core Processor (32 Threads)

Issue description

Related: #77378 (Might be caused by this).

When a project is launched with display/window/size/mode set to Fullscreen the main window will instead open in Exclusive Fullscreen. Moving the window in place seems to fix this, but I'm hesitant to call that a proper solution:

I.e. add MoveWindow(...) after creating the window here (or during it):

godot/platform/windows/display_server_windows.cpp

Line 4311 in 9d089fe

WindowID main_window = _create_window(p_mode, p_vsync_mode, p_flags, Rect2i(window_position, p_resolution));

It might be enough to send one of the messages that MoveWindow does https://learn.microsoft.com/en-us/windows/win32/api/winuser/nf-winuser-movewindow#remarks but I haven't tested.

Steps to reproduce

Open a project on Windows with display/window/size/mode set to Fullscreen.

Minimal reproduction project

N/A

[Yadnesh-Kulkarni]

@Lielay9 The expected outcome for this should be to have a borderless fullscreen for Fullscreen mode and complete ownership of display for exclusive fullscreen mode right?

[Lielay9]

@Lielay9 The expected outcome for this should be to have a borderless fullscreen for Fullscreen mode and complete ownership of display for exclusive fullscreen mode right?

In practice, yes. You can find the details of how that is implemented here, where the window is created...:

godot/platform/windows/display_server_windows.cpp

Line 3884 in 1f9e540

DisplayServer::WindowID DisplayServerWindows::_create_window(WindowMode p_mode, VSyncMode p_vsync_mode, uint32_t p_flags, const Rect2i &p_rect) {

... and here where the mode is changed:

godot/platform/windows/display_server_windows.cpp

Line 1374 in 1f9e540

void DisplayServerWindows::window_set_mode(WindowMode p_mode, WindowID p_window) {

[Yadnesh-Kulkarni]

Okay. I am halfway through debugging this. I will revert once I have any update.

[KoBeWi]

Sounds related to #60665

[Yadnesh-Kulkarni]

Looks fairly similar or may even be a duplicate. Once I can debug through play window, I can be sure. Will update here as soon as I have a lead.

[Yadnesh-Kulkarni]

Should Fullscreen mode have a Titlebar while displaying? If not then turning on Borderless Window property in property manager seems to have solved this. Though, I think turning on borderless window by default while turning on the Fullscreen mode should be the right solution for this.