I'm having trouble installing a brush set I downloaded from DeviantArt. I've unzipped the file, but when I try to drag the folder to GIMP's brushes directory, it gives me a prohibitory symbol and won't copy it over.

I'm running MacOS 10.14.3. I'm hoping this isn't just a Mac thing. With the current security protocols built into the OS, it takes an act of Congress just to get GIMP to launch every time I want to use it, since it's not a "verified app publisher", and they took away the "Always Open" function in security preferences.

I've identified part of the problem: the permissions on the folder are set to Read Only. The problem is, I can't seem to change the permissions to Read & Write. Would deleting and reinstalling GIMP solve this?

Caveat - Not a OSX user only a poor-ol linux fan and liable to remain that way. But I do have an old OSX VM to see what it is all about.

That reads like you are putting the brushes in the Gimp system folder - some long name in Applications/GIMP-2.10/...etc. That is read only.

If you look in GIMP-2.10 -> Preferences -> Folders -> Brushes there should be two entries one as above (or similar) and another for your Gimp user profile. /Users/your_name/....etc... As in the screenshot.

An alternative is make a folder for new brushes somewhere where you definitely have permissions and same place as before Edit -> Preferences -> Folders -> Brushes add that location. Same preferences dialogue to add path.

Thank you! That totally did the trick!