The browser captures the mouse and gets the focus as soon as it hovers over the web contents.
The browser shows a blinking cursor and then the TChromiumCore.OnGotFocus event is triggered. The QT6 demos set the focus on the TCEFLinkedWindowParent instance after that.
This issue only affects the QT6 demos using browsers in normal mode.
Browsers in OSR mode or using GTK are not affected or have workarounds.
The CEF project has 2 open issues about the focus in Linux : #2026, #3304
The #1856 issue could also be related.
cefpython is also affected.