Minecart/x-ray glitch

If you activate an elytra while midair (jump twice) then quickly after that get in a minecart, you will be stuck in crawl mode inside it and can't move. You can still sneak to get out. You can also use this to get a small x-ray view, shown in an attached image while facing down at any angle other than straight down, but the minecart has to be pushed off of a rail for the x-ray to work. Also, the minecart has to be on a block. If it's falling, you get out of crawl mode automatically.