I can't speak about KDE in particular, but I use a command line program called wmctrl to size windows to specific pixel dimensions. https://linux.die.net/man/1

I can't speak about KDE in particular, but I use a command line program called wmctrl to size windows to specific pixel dimensions. https://linux.die.net/man/1/wmctrl https://linux.die.net/man/1/wmctrl