I updated a world of mine, that was created on 1.13.x and updated always on mayjor releases or pre-releases.
When I first entered the world it was all rendering stange from a distance of me. When I got to the level everithing was looking very strange. I'm 100% sure that this was not a texture pack because i did not have any instaled on this computer.
The Bug is when you look to every block naturaly generated or placed by you it will render like I've mentioned.
Related issues
Attachments
Comments

Hello! This looks to be a duplicate of MC-1794. Try following the workaround given on that report; it may fix your issue.