A minor redstone repeater client side texture glitch.
So, I was playing with redstone and stuff like that. I decided to place repeaters and stuff in random positions. The second repeater's movable torch turns into a bedrock texture on its side.
These images were the result of using a lever and 2 repeaters, works on any game mode,
To perform this glitch, do the following pattern below:
/ _ii _i
key: / = lever, _ii = repeater facing right, _i = repeater facing away