When you put a Fence Gate between a Fence and an other bloc (dirt or stone for instance in my experience), the Fence gate texture is missing on a side (looking from the other bloc, "in" the gate).
Hope it will be solve even though it's a minor bug 🙂
Sorry for my frenchie english ^^'
Yes this happens for me, also if you place the fence gate between two normal blocks then the gate texture is missing on both sides.