Used this for a small linux GUI proof-of-concept.

I really liked it. It was awesome to use something I'm familiar with (Next.js) and have it drive the UI. Resulting application was indeed about 1MB after all said and done.

Interesting, but say good by to consistency across platforms.

The whole reason electron was created is because using a random unknown browser on the OS has random results.

Can you share any insight in the cross-os implementation inconsistencies of those browser engines?

Not a front end developer, and I do not know much about it, but I imagine that native engines would be Edge on Windows 10, Safari on iOS and whatever is installed on Linux by default - usually Firefox. From here you would need to figure out the differences between those engines with something like caniuse. Like support for service workers etc.