Trimmed armour has overlap issues on the item texture

If an armour piece is trimmed, the item has slight issues where the trim and armour textures meet, but only on the side.

Example: Iron Boots with Redstone Wild trim.

Take note of the lines on the boot.

 

Steps to recreate:

Get any armour piece, trim, and material

Combine in Smithing Table

Hold the resulting item, and look at the sides of the texture, where the two overlap