same here with version v0.8.1 on archlinux

This is probably related to rclone/rclone#7864

I was able to successfully log into proton drive today, on flatpak v0.8.3.

I was also able to login successfully yesterday, with flatpak v0.8.3

Also note, if you are using 2FA for your proton account, use the code that has only just changed giving you the longest amount of time (30secs or near), as the initial login did fail for me due to it taking awhile, resulting in that 2FA being out of date.

I was unable to login before when I was using the AUR packaged version 0.8.3-1. The reason it failed to login was linked to the 2FA box, I was unable to select it and so couldn't input the code. (no select box was present or could be seen for me to use)

Hmm... Doesn't work for me, tried several times.
Using Flatpak v0.8.3.

On another note, isn't this duplicate of #167 ?

Same experience. cant login. 0.8.3 snapcraft on Ubuntu.
I also tried with 2 factor on.

I had the same problem on Linux Mint Debian, snap version. I set up 2FA for the first time on Google Authenticator. It still didn't work. I checked my Proton Drive account info in my browser. It had my Proton.me email address listed instead of the Email address that I used to sign up for and sign into my proton account. I tried logging in with the proton.me email address and the 2FA and it worked first try. It took a really long time, so i walked away for a while. When I came back I was logged in. I closed the app and opened it again and I'm still logged in. Later I'll find out if my login survives a power cycle.