Sharing it here (pycharm related), had this issue but found answers on other forums:
I'm here in 2022, because same thing started happening to me while using Pycharm after an regular update. Neved had this problem but aparenttly it now became one. Is was happenning only in Pycharm and not any other application.
Came here obviously looking to read it was a bug, it is not necessarily is the case and at max, a setting running a little different. With a little help of the existing comments, just solved by:
- Checking if the insert key was under Settings-> keymaps -> Toggle Insert/Overwrite.
- Pressing it on my keyboard once. (i'm running manjaro/gnome, togglet it by pressing Fn+delete keys)
- It should work on smiliar plataformos, afterall all JetBrains products are quite similar.
- In other cases maybe just removing the keymap will resolve the issue at all :)