EDIT: With further testing, I discovered highlights spawned in BEFORE the player client joins/is loaded are not visible. Any new highlights spawned in during gameplay work fine.
Highlights are no longer displaying in the Roblox client. They appear fine on studio though. I first noticed this roughly 2 days ago:
Windows 10 Pro - Intel i7-7700k @ 4.8Ghz, 32GB, GTX 2080 super
Beta features enabled: All currently available aside from Non-strict scripts by default.
Update:
testing with the command line in-game shows that highlights that are already spawned in before the player joins/client window loads are not visible. (Screenshot counts present highlights and shows there are 6, but I cannot see them)