Hi all, I'm currently working on a project that suddenly has begun giving me this error that only happens on Chromium browsers, and only happens on non-incognito tabs, and also only happens after a normal refresh (aka f5), while everything works after a cache refresh (ctrl + f5). I have literally tried commenting out just about anything, step by step from the code to see where it goes wrong but I just cannnot for the life of me find the issue. To add, this only happens on next build & next start, whereas next dev has no issue with it and I cannot reproduce it.

I have a few useEffects in _app.tsx , but commenting those out does not help. I've tried debugging server side, client side, I've tried bisecting pieces of code step by step, only to just have this error always. It feels like Next.js is missing __NEXT_DATA__ at a point and errors out, but why would this happen? Does anyone have any idea on tackling this error?

Next.js version: 13.5.6
Using pages router (working on an old codebase)