Is there a way to fix all my disappearing stuff? Half the time I can see any chests and sometimes my signs are there.
on your minecraft launcher click "new profile" on the left. Go down a bit and see "Use Version" click the down arrow and choose 1.8.9.
The chest problem also happened to me, but when i got optifine it fixed it, and my guess for the signs that maybe they are part of clearlag?
Signs animals and other things will not randomly despawn, you may have your client view distance set too low and or using a bad version on the server. We do support from 1.8 to 1.10.x however sometimes there will be issues, mostly visual though.