Hi,
Using Chromium on an arm64 rpi in kiosk mode for an hmi/tablet interface thingy.
When opening a new window (kiosk or not), the entire window flashes white before anything shows (including the title bar, etc). I've tried using the GTK+ theme,
the classic theme and also tried the "Bits + Pieces" theme.
When enabling "use system title bar and borders", the title bar and borders do immediately show while the window area is white before anything renders.
The flash also happens when opening a new window. I do not get a flash when opening a new tab.
I went through a lot of the command line arguments looking for a fix, using --gpu-sandbox-start made the flash disappear MUCH quicker, however this also completely killed GPU acceleration with:
[15303:15303:0510/085557.017928:ERROR:gl_implementation.cc(286)] Failed to load libGL.so.1: libGL.so.1: cannot open shared object file: Operation not permitted
[15303:15303:0510/085557.041601:ERROR:viz_main_impl.cc(152)] Exiting GPU process due to errors during initialization
This seems to be the default background color of the window before Chromium renders anything.
This behaviour also happens on my Windows machine with Chrome (current). Even with Windows & Chromium both set to dark mode, also tried the Just Black theme, the window flashes white before any of Chrome's UI displays. Edge maybe sort of does the same, however, the title bar comes in so quick it's not as noticeable. vscode, as an example of a Chromium-based app, does not do this, by the time the window first paints, the background is dark and already has the menu, sidebar and status bar background colors also shown.
System is Raspberry Pi 4B using custom Ubuntu with openbox/ligthdm, Chromium is currently v83.