When a Wayland surface with XDG top-level window role is brought to fullscreen before it has even been shown at all, then it seems that KWin reports an incorrect size in the ensuing xdg_toplevel.configure event. This is reproducible with VLC.git as vlc -f VIDEO_FILE. Oddly, the problem does not occur if the window is taken to fullscreen after it has already been shown in windowed mode.
I'm not seeing KWin xdg_toplevel.configure errors in console when starting VLC with '-f videofile' option vlc-git 4.0.0-dev-3556-g34b1d4f1ee Plasma: 5.13.1 Apps: 18.04.2 Frameworks: 5.47.0 Qt: 5.11.0 Kernel: 4.18.0-1-MANJARO OS: Netrunner Rolling Video: Intel 4400 Driver: xf86-video-intel 1:2.99.917+831+ge7bfc906-1 Mesa 3D: 18.1.2 Screen: 1600x900 Xorg: 1.20 Wayland: 1.15.0-1 Wayland Protocols: 1.14-1
Please provide a long with WAYLAND_DEBUG environment variable.
Jonas spoke to me about this one just a few days ago. We set the size to 0,0 in our configure event when maximised. Although normally this means "client should do whatever" the docs for maximized say > The window geometry specified in the configure event must be obeyed by the client. There's a Qt workaround patch as we're not the only compositor doing this, but it's us doing it wrong. I started looking into a patch already.
(In reply to Martin Flöser from comment #2) > Please provide a long with WAYLAND_DEBUG environment variable. https://paste.kde.org/pxtvhnyyc/skumns
This issue report is quite old. Can you please confirm, that it still persists with KDE 5.23?