After discovering MusicBrainz, my computer experienced significant issues. It appears to be a bug or a serious flaw in the app's programming. Despite only selecting a folder of music tracks on an external drive, the app's scanning process caused damage to all of the libraries on my Mac, including ones that were not related to music, such as my fonts, projects, and iPhoto libraries. It is unclear what triggered this malfunction.

These are the steps I did:

1. Open the app and select the folder I wanted to scan
2. Selected the tracks that needed to be scanned (total of 17,000) stored on an USB 3 external drive (4TB capacity at 5400rpm)
3. Everything seems to be working fine, I was able to see how everything was getting the metadata and album covers accordantly.
4. My other external drives (4TB at 7200rpm) started to be unresponsive. I was trying to activate some fonts on my fonts manager and I wasn't able to get to my Font library on that external drive, I went to check iPhoto and pictures were missing as well. 
5. I went to open the external drive to see if the files were deleted and the Musicbrainz app crashed! Understand that the External drive I was opening wasn't the one with the music tracks. 
6. I restart the computer and the external drives were fine with their files but now I needed to re-link all the libraries from scratch. losing all the folders and categories I used to have on my computer.

Bottom line I didn't lose my tracks or files, but all my libraries were corrupted after using the app. Libraries outside the drive I was scanning.