When the health boost effect runs out, it will play the hurt animation even for players in creative and spectator mode

To reproduce, run

/effect redstonehelper minecraft:health_boost 1

while in creative or spectator mode and observe the hurt animation that will be played a second later.

Probably relates to/duplicates MC-42000, which was closed as "Incomplete", probably for not being in English. I'd be glad to take over that one.