I know it sounds like a question I’d rather ask on Vivaldi’s forum, but from what I gathered it could well be caused by Manjaro having trouble managing the saving of passwords (since it does it in a different way than, say, Windows).
I’d like to know how to confirm — or infirm — that my OS is indeed the problem and not my browser.
Of course I’m posting the inverse question on Vivaldi Forum.
Thanks!