This is a weird and annoying bug. After using some tabs and software in Konsole and "escaping" the terminal software and "exiting" in some tabs by typing "exit" - Konsole holds letter "e" and you have to type it twice. I confirmed it on other laptop with Debian.
as you can reproduce it under debian too, then that would most probably be a kde bug, and would need to be reported to the dev's for kde, this page perhaps:
https://bugs.kde.org/