Hi,
I have no access to Office 365 webmail, so that I cannot check for the issue. Maybe, the website does not happy to see the text changed :)! Like Protonmail, If we change the text in some special element, it will stop loading.

I have updated the extension to add keyboard shortcuts for some options. You can try these:
- CTRL+ALT+NUM0: Toggle the OFF button. (Use this to quickly turn the extension ON/OFF).
- CTRL+ALT+NUM9: Toggle the ALL button (apply the extension for all websites).
- CTRL+ALT+NUM8: Toggle the DARK button.
- CTRL+ALT+MINUS: Do not allow the extension to run on current website (add to blacklist).
- CTRL+ALT+PLUS: Allow the extension to run on current website (remove from blacklist).