When I go onto Minecraft 1.16, Everything makes these weird stripes and triangles. I've tried restarting my computer. I don't have any plugins or mods. It seems to be more broken the further away you are from blocks to the point where entire walls are invisible. It happens mainly on Grass paths, Clouds, Maps, Stairs, Waterlogged Blocks, Slabs, Crops, Signs, and World Borders. It's also pretty rare, apparently. It happens on one of my computers but not the other.
This seems to be what's causing it: https://en.wikipedia.org/wiki/Z-fighting