I'm using Proof General in Emacs on Aquamacs and every time I write a period (".") everything is executed (up to that period). It seems like an electric behavior but it's not. All other keys behave normally.
I know that this is some mode that started when I accidentally used some keybinding. If I restart the session the effect will stop, but I would like to know the keybinding to make it stop (or to make it start).
Do you know what this mode is called? I can't even find it online.
In general, if you're stuck in a minor mode that you don't know the name of, you can run:
M-x describe-mode
This will list all currently active major and minor modes, with a description of each. From this, you should be able to figure out which one you need to deactivate.