No longer possible to enable debug mode on a per-plugin basis?

I raised a very similar problem once they trimmed this support

There is a workaround that works without setting app.debugMode(), though.

If you add at the end of main.js

(newline)/* nosourcemap */(end of file)

then, the sourcemaps won’t be trimmed, even if debug mode is not enabled

I even made an esbuild plugin that adds this magic string on npm run dev

Maybe you can consider adding this magic string within your Hot Reload plugin. I can send a corresponding PR, if you are interested.