1.1
release
Square Offhand Slot
Makes the offhand slot square like the hotbar.
32
Square Offhand Slot
The offhand slot has rounded corners, unlike the hotbar. So I made the offhand slot square like the hotbar! (Now on Modrinth!)
Is your main hand left? It also retextures the right offhand slot! Also uses the pre-1.14 textures if you are using a version below 1.14.
If I don't have the latest version of Minecraft supported, just use the latest version of my pack, it should work unless they changed the pack format again.