The Gradient Tool rotates the camera on Mac instead of painting the Gradient End Value. I wasn't able to test in Main on a Mac. There were no issues on Windows in 4.23.1, 4.24.3 and 4.26 Main.
Found in 4.24.3 CL#11590370
Reproduced in 4.23.1 CL#9631420
1. Create a new project on a Mac.
2. Import a skeletal mesh that can be painted with cloth phsyics.
3. Create cloth data for the mesh and select Activate Cloth Paint mode.
4. Under Cloth Painting set Tool to Gradient.
5. Try to paint the Gradient End Value.
Result: The camera rotates.
Expected: The Gradient Tools works as expected.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-89781 in the post.