Bit of a weird one, I have no clue if it's intentional or not, but flying into a contraption that contains a copycat slab oriented vertically will drop a player's creative flight. No logs are generated on the client or server from this interaction.

Minecraft: 1.19.2
Fabric: 0.15.3
Create: 0.5.1c
Copycats+: 1.1.1

If you have any further questions I'd be happy to respond.

theres been a few updates to the mod already. you should update the mod then see if it still happens

server is getting its mods updated in a few days, ill revisit this when the updates are complete