Duplicate of MCPE-222915.
I am unable to reproduce in the latest snapshot, 25w33a, and also 1.21.7, which you marked as affected. Could you please provide reproduction steps or a video of the issue happening with the F3 debug screen enabled?
If your Smooth Lighting setting is enabled, this ticket would be a duplicate of MC-64678, which was resolved as “Won’t Fix”.
If the issue you’re experiencing takes place in the cases J Cardwell mentioned, this ticket would be a duplicate of MC-153385.
Duplicate of MCPE-222915.
Could you provide a video if the bug happening or steps to reproduce, please?
Can reproduce in 1.21.8
Works fine for me in 1.21.8, has it happened again?
Can’t reproduce either
Seems like you have Touchscreen Mode enabled. Please try deactivating it:
Options → Controls → Mouse settings → Touchscreen Mode: OFF.