Transporting a villager in a boat. It had an Armorer Profession. I needed to log out for some IRL stuff, and came back online afterwards. However, when I logged back in, I was kicked out of the boat. I couldn't right click to get back into the boat at all. As this was happening, the villager lost his profession. Which in-turn, created the texture error. I could see his undershorts and knobby knees. I logged back out and in, thinking it was just a slight error, but the texture didn't fixed itself. I right clicked several times to get back into the boat again. At this time the texture flickered on and away again (from having pants to having no pants to having pants). After that I was able to re-enter the boat. At that time I had noticed the texture naturally fixed itself as I entered the boat.

Also, yes, I do know there is another open bug of the texture issue (which I found here: MC-175937) But nothing about the, being kicked from the boat, before/while villager lost it's profession, and not being able to get back in until after it was done.

Edited 9/22/2020 : I have also noticed that this also happens with sheep in boats as well.