Actually, the app was both NwJs AND Electron based, but at some point, but I dropped NwJs support to clean up the code and only kept Electron.
But all Electron related calls are easy to locate and you could use compiler conditions (just like I did before) to use something else (ie. to open a system dialog or display a page template).
Tauri is even smaller than NW.js (I think ~600kb hello-world binary size) but uses Rust in it's toolchain way under the hood to build, so take that as either a positive or a negative.
https://github.com/tauri-apps/tauri
NW.js is essentially lighter-weight Electron.
https://github.com/nwjs/nw.js
Would be neat if it was a straighforward implementation and produced tiny self-containing cross-platform binaries.
Disclaimer: I also have no idea how gamedev works though, so this might not be applicable