If a log block is above the player's head (2 blocks above the ground), then try to break it (I tried break it by axe), you can see the very high frequent flashing and other animation error.
This problem still exists after turning on the "Outline Selection" option.
This problem does not occur on log blocks that 3 blocks above the ground.
Thank you for your report!
We're actually already tracking this issue at MCPE-85467, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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