MC v 1.9.4
Forge 1963

Leaves have what look like Bounding Boxes as seen in the first few pics granted some leaves I am not looking at and see it...noticeable in the 2nd picture just slightly off to the upper left:

Logs have what looks like Texture sharing I think or just slightly off its axis/scale in the pics further down
For most of the pictures I looked at Vanilla as it seems more relevant.

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I tried different settings to see what the outcome was in the first few pics but then I decided to look at other logs so I could see if others were having the issue too

I can't reproduce this right now. However, I know of the problem, it has cropped up intermittently before while I was testing. Seems completely random and rare, couldn't figure out why it happens.

Closing for now, but I'll keep it in mind.