Firefox on Linux sourcemaps protocol error

Developer Tools
#1

Since about April 2023, I have been unable to edit css generated by SASS in Firefox’s DevTools Style Editor. If I click on a file listed by sourcemap, I receive the following error:

Error while fetching an original source: unsupported protocol for sourcemap request file:///home/.../sass/partials/_normalize.scss
Source URL: file:///home/.../sass/partials/_normalize.scss

... replaces actual path redacted for security.

The sourcemap file is syntactically correct. It has the /*# sourceMappingURL=<css_file_name>.css.map */ syntax. Working with webkit browsers such as Thorium, Chromium or Brave presents no error.

Through Google and DDG searches, all I have found on this topic is a similar unanswered post on superuser.com.

What is the extra step to accessing sourcemap files in Firefox DevTool Style Editor under Linux?

#2

Looks like you’re hitting this error: https://searchfox.org/mozilla-central/rev/aa8a99510c0686cdf9d42fb4b8f6d968884c961d/devtools/client/shared/source-map-loader/utils/network-request.js#20

Would you know what protocol your sourcemap file is using?

1 Like
#3

No, I don’t. I have been thinking file:// is the protocol and DevTools wants something else.

#4

Is there anyone with insight to resolving this issue?

#5

noticed it also fails for webpack.