Failed to execute 'btoa' on 'Window' while setting up WebDAV sync

[FrenchVillain]

Hey all,
I've recently discovered SP and saw it could sync with an online Drive. I would love to make it work with my Proton Drive as I already have one. I have tried to add the URL of a folder with editing rights as the base URL inside of which I located the sync folder. This is because Proton will not let me share the root folder of my Drive.


I then added all the information to the sync section of my settings. However, when I try to sync, I get a the following error: Invalid CharacterError: Failed to execute 'btoa' on 'Window': The string to be encoded contains characters outside of the Latin1 range..

I get the same error on both my mac laptop and android phone. The blurred part of the base URL contains uppercase and lowercase characters, numbers as well as a # and a -, could that be part of the issue?
If anyone has any idea on how to fix it?
Thanks!