When you ride a horse and detach from a lead connected to a fence, the rope on the fence doesn't go away.

I was playing survival when I tried to see if I could detach my horse from a lead when riding it, it detached, but when I came back I was surprised to see there was still a lead rope on the fence.

NOTE: This was in a multiplayer survival server.

This may be OptiFine's fault as I use it.