Edit: None of the answers I got work so I went ahead and filed a bug in KDE bugzilla: https://bugs.kde.org/show_bug.cgi?id=502901
Neither CTRL Q or CTRL W work for me. I set a hotkey for the window operations menu in Settings app > Shortcuts > KWin > Window Operations Menu, but then pressing the close button in the context menu that shows, closes the window of the other window I was focused on and not the debugger.
@TheTwelveYearOld I don’t have a solution but you may be able improve the quality of replies by not mentioning titlebars at all and asking how to close the Kwin debug console without mouse input
People are still overlooking the goal regardless…
Yeah hindsight is 2020.