Open Brave (Mac or Windows, doesn’t matter).
Navigate to fastmail.com and log in with your account (create an account if you don’t have one, it’s free for 30 days)
Once logged in and viewing email (send your new email address mail if there is none) click the radio button next to some mail and attempt to click the Archive button at the top of the page (or any buttons for that matter).
Shield can be up or down (doesn’t seem to make a difference) and sometimes the buttons within the fastmail.com interface don’t work. They do, however, work always on Chrome and Safari.
|OS Platform||Microsoft Windows|
Only extension enabled in Brave is bitwarden and without any enabled, buttons in fastmail page are intermittent.