Firefox

I've just switched from Brave to Firefox on Android and so far liking it. There's one issue though. I use Bitwarden for my credentials & SwiftKey as keyboard. When I go to a website that asks for credentials, the Bitwarden button shows up above my keyboard to unlock my vault, as expected. I click it, unlock with fingerprint, and select the credentials. So far it's as expected and the same as Brave. However, when I select a credential, it goes back to Firefox, but then refreshes the page; so the credentials are gone. Luckily the credentials then show up above my keyboard as I've unlocked the vault, but after some time of inactivity I have to unlock again and the problem reoccurs.

Any idea how to resolve this?

/edit: looks like a long outstanding bug in Firefox, see here https://bugzilla.mozilla.org/show_bug.cgi?id=1807364