currently this only affects one horse I have and I'm unsure of why, still its a bug none the less. I can not use a lead on this horse, at first I thought it was broken for all horses, but after testing on all my other horses it was fine but for some reason this one horses wont let me lead it, every time I try I just ride it... anyway I tried to take armor off it, saddle off, just anything to see what was messing it up and I couldn't lead it regardless.. my only thought is maybe I wasn't the original owner as I am on a realm so there could be a bug with leading other peoples horses but I have not tested this.. anyway now you know.