all upgrades can suddenly develop random weird results, but without the code its hard to know exactly why, but the fact behaviours change, it could be expected as it resolves another issue or it could be a whole new bug, its not like there arent plenty of them
It sounds like this issue which should be fixed in the 6000.0.3f1 release.
For now, simply set the ContactThreshold to 0 to turn this feature off and it’ll fix the issue. You can restore it to its default of “0.01” later if you wish.