Weapon models and other player models keep disappearing

Since over 1-2 months now, my weapon keeps disappearing quite regular, or gets invisible since I can still use it. Additionally, all player characters get transformed into polygon shapes, with no clear models anymore. In the latest game I played some enemy player models just disappeared completely. Imagin my confusion and frustration when I got shot by a floating gun. So, my weapon disappears and the other players their model disappear but their guns remain. Really nasty annoying bug.

The cherry on top is, when I disconnect from the server, I get a black screen and have to Alt+F4.

Three month is quite some time to fix this problem already so please fix with next update!