Brush clip slicing doesn't work whenever slicing in Left sided Othrographic view mode.
Tested in 4.21.2 (CL - 4753647), 4.22.3 (CL - 7053647), 4.23 (CL - 6837701), 4.24 (CL - 7095658)
Expected: A geometric slice is made to the brush and a new edge is made
Result: An error pops up "Modifier (Brush Clip) : Unable to compute normal for brush clip!"
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-76649 in the post.