Mail 1.10.0 - Unknown tags

I have tags on some emails, like Hasnoattachment,Unsubscribe,Newsletter.

I assumed there would have been a filtering, but nothing happens when I click on it, either in Message List or in Mail Headers, in the Reading Pane

What added the tags ?
What is their purpose ?

BR

Hi,

those tags are from some other IMAP clients or your IMAP server. You can try some internet research to find out what application adds them.

Nextcloud Mail doesn’t add those. They already existed.

Hope this makes sense
Cheers

Ah yes, all those mails are from the same provider, which uses Zimbra. Thanks for this, I didn’t think about the server tagging.