Honza, Kyle, would you be able to try to reproduce this and share a minimal test case? Anecdotally, I've heard from others that this can be a problem.

I put together a really simple example running express-js with some static assets, a sourcemap, and http basic auth and I couldn't reproduce. I will try again compiled js files instead of css since that is what the original bug was about, but I'm not sure what difference that would make.

Thanks Kyle. Could you share the example in maybe a github repo?

(In reply to Jason Laster [:jlast] from comment #6)

Thanks Kyle. Could you share the example in maybe a github repo?

See here: https://github.com/kylethebaker/ff-bug-testcase-1404245

The basic auth user/pass combo is (in classic fashion) user:password

I'm currently on Firefox Nightly 66.0a1 (2019-01-24) (64-bit)

This seems to be working with sourcemaps generated for be css and js assets

Thanks for the example Kyle!

JS seems to be working for me. I can see script.ts (source mapped from script.js) in the Debugger panel.

I can also see the styles.css (in Style Editor) nicely formatted (not the same as the HTTP request response data), but not sure if source map is used in this case.

Screenshot attached.

Jason, can you check the CSS mapping?

Honza

I'm not sure what to look for wrt the scss -> css mappings. Martin, would you be able to take a look?