The bug
When crawling, the player can break a block 5 blocks below itself clientside, but not serverside. As such, the block appears to be broken successfully, but it immediately reappears again and doesn't drop. This happens both in Survival and Creative mode.
How to reproduce
Get into crawling mode
Dig a hole below you (without falling into it)
→ ❌ The fifth block seems to break successfully, but doesn't
Examples
Attachments
Comments 14
Video attached to the bug. Apologies for low FPS at the beginning; I'm on a low-end computer. I'm also on a Linux based OS. Ubuntu to be more specific. Video was recorded in singleplayer.
MC-243463 has been assigned a "Mojang Priority" so this ticket should probably be resolved as a duplicate of it.
I cannot reproduce this. Could you provide a short video showcasing the issue? If possible, enable the F3 screen.