I was annoyed by users registering with disposable/throwaway/temporary email addresses (like mailinator),
so I decided to develop a plugin to prevent that.
The ACP is just a textarea where you can paste your email domains that you want to blacklist (one per line).
Example of a maintained blacklist.
Edit: It can now also use isTempMail API to check the domain.
If an user register (or update his email address) with an email address that is blacklisted, it will block the registration with an error message.
npm install nodebb-plugin-email-blacklist