The bug

Villagers will sleep briefly after it is daytime if you take their bed while they are sleeping in it.

Steps to reproduce

1. Go to a village
2. Wait for nighttime
3. Sleep in a bed occupied by a villager

-->  Notice the villager tries to sleep in it after you wake up.

Additional Information

I have only ever seen it occur in survival mode, though it is likely it happens in any gamemode other than spectator.