Characters and numbers sometimes not shown in software after being typed-in

I sometimes notice that when I am typing in form fields in Firefox (and possibly in other software I’ve forgotten, could be Iotas and/or Apostrophe) that the last keystroke isn’t immediately shown. Only another keystroke reveals the one before.Putting the cursor somewhere else inside a word behaves similarly so I don’t really know the cursor is there. There seems to be some lag or something?

It’s super annoying, does anybody have an idea what could cause this? It’s only happening some of the time. If you need more info, please be so kind and ask, I’ll try to provide it.

I just recently had a case where the cursor was not displayed in the terminal window.
A full update followed by a reboot solved it.

Have you updated recently sudo dnf upgrade --refresh?
Have you rebooted recently?