When creating a resource pack for custom tooltips, the background will not scale properly when hovering over and item. This resource pack was made by directly copying the vanilla textures and .mcmeta files, only modifying the hue of the .png files.

Steps to Reproduce:

1. Download and apply the resource pack:
   custom_tooltips.zip
2. Get an item with the custom tooltip:

   /give @p light_blue_wool[minecraft:tooltip_style='jineric:blue']
   

Expected Result:

Because this pack uses the same exact files as the ones used in vanilla, it would work without modification or scaling issues.

Observed Behavior:

The resource pack functionally works, but the end result is unexpected and incorrect.

Screenshots/Videos:

Vanilla

Resource pack

Notes:

Closely related to MC-276301 and could be the same root cause, but the end result for resource pack authors differs from the issue present in vanilla item tooltips.