Custom collision presets will not be saved properly to foliage after closing and reopening the project. Additionally if you make changes to any collision preset in project settings, the foliage will not update its setting till after you reset the collision settings.
Found in 4.19 CL# 4033788, 4.20 Preview 3 CL# 4135216, 4.21 CL# 4157973, and 4.22 CL# 4589258
The foliage collision preset settings will be set incorrectly
The collision settings would be the same
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-61103 in the post.