Whenever you hop into a berry bush and activate your elytra to go into fly mode, your curser points at the wrong spot. You could be looking at a block at the same level as the bush, however if you try and break blocks you will break things 2-3 blocks above the bush.

How to reproduce
1. Place a 3 tall wall next to a berry bush
2. Jump into the bush and activate your elytra
3. Look at the bottom block of the wall, and start mining
4. You will notice the blocks above where you are looking, are being broken.

Expected result
The block that you are looking at, should be broken.

It appears the game doesn't think you are actually in fly mode, instead you are standing up normally.

Video demo: https://youtu.be/AcUTl8hKU-U?t=258