Hi > 1. Settings -> Configure Keyboard Shortcuts > 2. Search dup > 3. Assign Duplicate Selected Lines Down to Ctrl+D > 4. Accept warning about replacing existing usage of Ctrl+D.
At least with 21.04 I cannot reproduce this, kate returns immediatly. Best Norbert -- PREINING Norbert https://www.preining.info Fujitsu Research + IFMGA Guide + TU Wien + TeX Live + Debian Dev GPG: 0x860CDC13 fp: F7D8 A928 26E3 16A1 9FA0 ACF0 6CAC A448 860C DC13