Summary
Shulker Boxes have weird pixels underneath them on hotbar, strangely this issue doesn't affect 1st hotbar (doesn't matter what colour are Shulker Boxes or what texture pack player uses).
Steps to Reproduce:
Fill your hotbar with Shulker Boxes.
Review them.
What I Excepted to Happen Was...
Shulker Boxes appear without any issues on hotbar.
What Actually Happened Was...
They have weird pixel underneath them except 1st hotbar.
Thank you for your report!
We're actually already tracking this issue at MCPE-41738, so I will resolve and link this ticket as a duplicate.
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