SUMMARY 1) This does not happen with Latin letters 2) This does not happen with Cyrillics in other Qt apps STEPS TO REPRODUCE 1. Open Kate 2. Start typing Cyrillic words OBSERVED RESULT Multisecond delays between input and letters showing up EXPECTED RESULT Fast input, just as with Latin SOFTWARE/OS VERSIONS Operating System: openSUSE Leap 15.1 KDE Plasma Version: 5.16.90 KDE Frameworks Version: 5.62.0 Qt Version: 5.13.1 Kernel Version: 4.12.14-lp151.28.20-default OS Type: 64-bit
Appears to have been fixed in 19.08.2, at least cannot reproduce now :)