Hazel is listed as supported on their Github page but that does not seem to be the case.
https://github.com/lra/mackup?tab=readm ... plications
Apparently, the way that Mackup works is that it creates symbolic links from various files in your ~Library/Application Support/ directory and puts the files on your iCloud (or other cloud) drive.
For those wondering, it's both for backup (putting all files on a cloud drive) as well as making it easy for two computers to use the same configs.
For whatever reason a lot of apps don't like symbolic links or putting files on the iCloud drive. Hazel is one of them.
When I originally began having the problem, Hazel support was very helpful in trying to diagnose the problem but ultimately they recommended creating a new Admin account to see if the problem was isolated to a specific account.
The problems disappeared on the new account and I figured that the issue must be a corrupted plist or some other file or maybe even some permission issue I accidently introduced.
However, a few weeks into using the new account, I reinstalled Mackup, and that's when everything quit working.
Again, thinking this must be a permissions issue I was digging everywhere that Hazel and these other apps that quit working might be sharing data in common directories.
That's when I noticed all of the symbolic links in Application Support and, more importantly, all the apps that were having issues (Hazel, Bartender 5, Transmit, CleanShot, etc) were all symbolically linked.
When I uninstalled Mackup (which reversed the symbolic links and put the files back where they're supposed to be) all the apps that had stopped working correctly suddenly began working. All my Hazel drives returned, all my rules returned, etc.
Now knowing that something with symbolic links may have been the culprit, I was able to narrow down my research and I was able to dig up a recent issue/bug report on Github asking that Mackup remove Hazel as a supported application and that report mentioned a post on this forum.
viewtopic.php?f=4&t=11615&p=28576&hilit=mackup#p28576
But since that forum post is from 2016, I figured I would create an updated post with some additional information in case anyone else runs into a similar issue. Hopefully, I've added some more keywords that people might search for on this topic which will help them find an answer.
Maybe I'll save someone a few hours or days or even weeks trying to figure it out.
