I enabled the 'Junk controls' in Thunderbird and then trained the built in filter to recognise Spam/Junk and send it to the Junk/Spam folder. Now it works very well. Please remember there is a difference between honest business requests and true spam. You woud not want someone to get reported as spam for an email just because you are not interested as it could effect their business. But some spam is unwanted and offensive and needs reporting. I have set up a few days grace so I can check that nothing good went to wrong folder - rare, but has happened. After X days the folder contents get deleted. * https://support.mozilla.org/en-US/kb/thunderbird-and-junk-spam-messages but Signal Spam is entirely different - you create an account with Signal Spam so you can send them reports of potential spam and they can send you newsletter reports etc. https://signalants.signal-spam.fr/sign_up