Problem loading custom brushes

Software GIMP
1

I’m running GIMP 3.0.2 on a Mac M4 Mini running Sequoia 15.4.1. I have downloaded some custom brushes, and put them into the folder specified in the GIMP settings. I have verified the folder several times. Unfortunately, none of them show up in GIMP. I have closed and reopened GIMP. I have tried the Refresh Brushes at the bottom of the Brushes panel. I have closed GIMP and erased its cache and reopened.

Can anyone suggest what might be going wrong?

2

caveat, I use linux 3.0.2 appimage

Although you have already checked the brush folder location several times, it is still worth checking in Preferences → Folders → Brushes for the actual path that Gimp 3 uses.

…but it is most likely the type of brush. Are these PS something.abr brushes ? Old types work here, (I think type 5 and earlier) but any recent PS brush containing actions and other PS specific stuff are not supported.