When starting Sourcetree, the remote button is shown with an exclamation annotation, supposedly because Sourcetree does not know how to open the remote in a browser. However, if I open the repository settings and change the account type from "Generic" to "Bitbucket" or "Github" and do not edit the SSH url to the remote, then save the change, the annotation goes away and Sourcetree can successfully open the remote. If I then close Sourcetree and reopen, it has forgotten the repository type and set it back to "Generic" and cannot open the remote browser. I can repeat this any number of times.
Using Sourcetree 3.3.4, but was not allowed to select that below.
I have recorded a video and posted it here: https://drive.google.com/file/d/1vyqWNbmuezH7xQ_SkudXHkXXCfk02AlX/view?usp=sharing