It happens both in singleplayer and multiplayer, when i begin playing at one point my hud disappears, it comes back when i turn from a window to a full screen but all item textures disappear, same with the pause screen, i didnt press f1 because when i do nothing happens, it happens to me since 1.21.6 onward, when the items reappear when turn a bit dark
Open GL error, which operating system are you using and processing unit?