In the [docs for email setup](https://docs.gitea.com/administration/email-setup) `mailer.IS_TLS_ENABLED` is mentioned which was replaced by `mailer.PROTOCOL` in release 1.18.0 according to https://blog.gitea.com/release-of-1.18.0/ . This change wasn't reflected in the docs for email setup. I just replaced the deprecated mailer setting.
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