More loosely relates to these issues: MC-144009 MC-145821 MC-164001 MC-165403
The bug
If translucent pixels are present in any of the two sprites for the anvil text field, they are rendered completely opaque in-game, which is not correct.
How to reproduce
Download and apply the attached resource pack
Enter an anvil
Observe
Expected results
Translucent textures where the text is.
Actual results
Entirely opaque.
Linked issues
relates to 12
MC-270518
Scrollers in block UIs render translucent pixels as opaque
Resolved
MC-270051
Recipe book button renders translucent pixels as opaque
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MC-270519
"Error" textures in block/entity GUIs do not support translucent textures
Resolved
MC-270765
Bundle background does not handle translucent pixels correctly
Resolved
MC-109447
Inconsistency in transparency of GUI PNG files - only some can be transparent + hover-bugs
Resolved
7 more links
Can confirm.