Bug with arrows

I found this bug, that if there is too many arrows, one of them become black.

How to reproduce:

1. Shoot many arrows or make arrow - shooting mob shoot many arrows into the block.

2. You will see one of the arrows become black (it's a really rare chance)

Hopefully you understood me right

To explain it more clearly, I posted a screenshot down below. Sorry, if there is too many pics, I thought that my last uploaded pic didn,t upload.

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