I use Minecraft 1.12 w/ forge and Optifine
Mods: http://i.imgur.com/FojIle9.png
Texturepacks: http://i.imgur.com/3V5AE7Q.png
If I disable all resourcepacks, except unity - bug is still there, but if I disable only unity, it fixes
How it looks: http://i.imgur.com/OKmpEHQ.png

Unity doesn't even replace any files in the textures>entity>banner folder. I don't see how it could affect any textures.

Try having only Unity loaded as a resource pack and restart your game. Try rearranging the resource pack load order. Try downloading the latest Unity from the repo. Click the green "clone or download" button, then download zip.

Looks like it does Faithful + Unity, odd thing, but If I use them separately, the both work

If I disable all resourcepacks, except unity - bug is still there

You said you already tried it with just Unity. You lied!

no, I just not reloaded my game that time, this time I did

Why are you using both a 16x and a 32x resource pack to begin with?

Some people like to watch the world burn.

because Faithful adds connected logs and, retextures some items, that Unity doesn't and grass is not patterned