ever since the 1.16 update, one of my creative worlds has been broken beyond repair

this issue never used to happen, but since 1.16 these white outlines appeared on one of my worlds and there was extreme lag being caused. Even using backup files didn't resolve the problem so it's definitely something to do with 1.16 and the following updates that came after, and nothing in the graphical settings resolves it either, and it happens whether or not you use the default texture packs, so I just leave the Clear Craft and Clarity ones on.

Please release an update that fixes the issue forever,

Nobody wants to experience this with their worlds and builds which they put a lot of time into putting together. It worked fine on version 1.15 and before.