Feature Request: Shortcut for Insert/Overtype Mode on MacOS

[ellapollack]

A text insert mode would mimic the behavior of the Windows insert key i.e. when a character is typed it overwrites the character ahead of it. Ideally there would be a keyboard shortcut to toggle insert mode as well.

This is useful for editing patterns written like "x--x---x--x--x-x".ring.tick = "x" since inserting text does not change the length of the pattern.