That sounds as a hardware glitch to me. What happens if you simply reinstall ibus?
sudo apt install --reinstall ibus ** Changed in: ibus (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1880262 Title: package ibus 1.5.22-2ubuntu2 failed to install/upgrade: installed ibus package pre-removal script subprocess returned error exit status 127 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ibus/+bug/1880262/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs