Running Vesktop on Fedora Linux 40 KDE on X11 with the command-line option --disable-renderer-backgrounding seems to fix my issues regarding messages "hibernating"/having a delay (only sending when Vesktop is focused). I don't use Disable Call Idle.
(By the way: https://github.com/Vencord/Vesktop/commit/d3b94fc4df6eec3f93a0689309760e2bb3e96249#commitcomment-142196978)














