KWin script for Picture-in-Picture in Wayland. Support Firefox and Chromium.
$ git clone https://github.com/joelkurian/kwin-pip.git
$ kpackagetool6 --type=KWin/Script -i ./kwin-pip
Then enable it from "System Settings" > "Window Management" > "KWin Scripts" > "PiP for KWin(Wayland)".
$ kpackagetool6 --type=KWin/Script -r kwin-pip