I tried to get Thunderbird working with Outlook.com mail. Thunderbird automatically recognizes the server information for Outlook.com and also that you need OAuth2 authentication.
IMAPS was working afterwards, but I was unable to send mails via the SMTP server “smtp-mail.outlook.com” which Thunderbird automatically used. I checked with this Microsoft site and everything seemed to be ok.
It took me some time to find out that the server “smtp-mail.outlook.com” does not seem to support OAuth2 authentication.
I set up my account in Thunderbird again, but this time I used the manual option. I entered the IMAP data mentioned in the above Microsoft link but used “smtp.office365.com” as SMTP server name.
This did the trick. Afterwards I was able to send mails from Thunderbird again.