Was testing out eM Client 9 and then installed Beta 10. Perhaps I never noticed it but it appears that em Client is having issues with my FastMail accout. I have set up an app password but when the software checks for email all I see is a spinning circle which it finally errors out.
Figured out the issue. I had to configure em Client to use SSL/TLS on special port (legacy). It would be nice to be able to use OAuth2 like Thunderbird 115 does for this account
We fully support that with Fastmail accounts with the upcoming eM Client version 10.
If you want to give the beta release a try, you can find out more here.
Once that is installed, go to Menu > Accounts and click on Add Account. Enter your email address in the automatic setup. You will be forwarded to the Fasmail website to provide your credentials, and then back to eM Client where the account will be setup correctly, and with oAuth.
I have Beta 10 installed here. All these accounts are already set up. Are you saying that I have to redo the set up all over again for Fastmail account rather than simply switch to OAuth2 in the current account?