No one else having the same problem here? In my CurseForge ticket I got to the conclusion that maybe only those who use GMX as mailing provider are affected. The question is: Does GMX block emails from Curse (although the sender addresses are added to the spam whitelist) or does Curse not send any emails to GMX?
Can someone please inform the responsible persons from Curse about this? It's really annoying.
I did report it, and the IT people from Curse talked to GMX directly to confirm that it's not a block on their side. I'll poke IT again and link the CurseForge ticket to have them look again.
In the mean time, can you do an experiment and change your email to a different domain (new gmail account or something) and see if you receive notifications? That would let us confirm that it's GMX vs some other issue, I think.
The IT people at Curse found a misconfigured mail server on Friday morning that was causing some mails to not have our standard identifiers -- we're whitelisted by GMX and some other providers, and without this, some of the mails got denied/spam filtered at the provider level. So yes, it was a problem with Curse in the end.
It should be fixed now! Let me know if you run into any more issues.