Maybe add some output when manifest is not valid ??

[StealthyKamereon]

Running npm run build with the default template will not output anything if the manifest.json is not in the correct format (for example: a trailing comma).

I know javascript as a whole is a joke but could their devs at least try to make it remotely bearable ?

By the way, background scripts don't work if the source file isn't located in the scripts folder which is very misleading with this:

Place any additional background scripts that are not directly declared in manifest.json into the /scripts folder.

[tom2strobl]

I know javascript as a whole is a joke but could their devs at least try to make it remotely bearable ?

You are aware that somebody put in hundreds of hours of their time without compensation so you can use extension.js for free, right? Show some respect. (I'm not the author of this, just a decent human being)

Running npm run build with the default template will not output anything if the manifest.json is not in the correct format (for example: a trailing comma).

Any properly set up IDE reports hard syntax errors.

By the way, background scripts don't work if the source file isn't located in the scripts folder which is very misleading with this:
Place any additional background scripts that are not directly declared in manifest.json into the /scripts folder.

Simply not true. My background script is not in /scripts and works just fine.