A raw proxy repo to github works on 3.26.1 and fails on 3.30.0. Both are fresh installs with just the github.com proxy added.
Install nexus, add raw proxy repo to github, and pull from it.
With version 3.30.0 get a 404
With version 3.26.1 it saves the file
Apologies for the inconvinience. Indeed, NXRM 3.30.0 shipped with a regression in raw proxy repositories, and the fix is ready for 3.30.1 - NEXUS-27013. Unfortunately I can not give any specific ETA for 3.30.1 release date yet, as it’s expected to ship with some other bug fixes. Perhaps you may want to downgrade to 3.29.2 in the interim.
There is now a patch available for 3.30.1 on the issue: