What is the bug?
The bug in question causes the player to get trapped and be unable to move off the block unless they break the dirt block they're standing on.

Steps:
1- Stand on a grass block and look down (don't move).
2- Use a shovel to turn the grass into path land.
3- Use a hoe to turn the path land into hoed land
4- You're now stuck

Not sure i was clear enough so, here is a video i made to help. https://youtu.be/WP3KpCY2ErM

Hope this helped, if there is anything else i can do let me know.
-OMG