Discogs id starting with [m are failing

Hi, I am not 100% sure if it really is as I describe it here, but anyway.
I noticed that whenever I try to name my files by an discogs release id starting with [m (e.h. [m54682]) I get an error rmessage:
"Error connecting to server: www.discogs.com
404: Not found"
At first I thought there was really an issue with the connection at that time, but I can try to do another search directy after that and to another id (e.g. [r1057669], same album but with a different entry), and it will work. Searching for [m54682] again will result in 404 again.
So far I am sure my description is correct, but I think this goes for EVERY discogs entry starting with [m.
Please check, thanks!

(Win 10 1909 home, MP3Tag v3.02)

Discogs IDs starting with "m" are so called master releases, as far as I understand something like a combination of different releases.

Might be, but why shouldn't they be found by MP3Tag?

It's because the master release [m...] page isn't formatted the same way as a release [r...] page that's why an [m...] number is invalid to use. It's really a basic "folder" page to contain all the different versions of that particular album/single/etc issued around the world over time.

It doesn't even have tracknumbers for example so the master release pages are basically useless for Mp3tag to use as a tag source compared to a release page.

The good news is every master release page does always link through onto several release [r...] pages, so it's just a matter of opening whichever release is right for your mp3s and using its [r...] number.

Maybe Mp3tag could be given some smarter error message to announce instead of a 404/error if a user tries to use [m...] number in that option, like: "please use a valid r number" or something so users don't think it's a connection issue.