Getting warning because of missing .map file

Question

I have included quill.min.js in my site (I have no reference to quill.min.js.map on my site)

When I debug the site, I see the following warning:

DevTools failed to load SourceMap: Could not load content for my-site/Scripts/quill.min.js.map: HTTP error: status code 404, net::ERR_HTTP_RESPONSE_CODE_FAILURE

Why am I getting this warning? quill.min.js.map does not exists on my server, I have only included quill.min.js. Do I need to include the map file on the server too?

Is this line: //# sourceMappingURL=quill.min.js.map just a comment or a reference to the map file? if it's a comment, then I don't any reference to the map file on my site.

Answer 1

A .map file is just a "helper" for debugging. If you have a "minified" JS-file (which is mostly the case in production environments), the .map file, as the name says, maps it to a better human-readable version.

So, in short, there is no need to have that file on you production server and you can ignore the warning there. (Indeed having it in production should be avoided.) But it is helpful in development environments.

The //# sourceMappingURL=quill.min.js.map indeed is both a comment and additionally has an own semantic which is evaluated by a browser to indicate the path to the map file for debugging purposes. Nevertheless, you can (and, in this case, should) securely remove it.