User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:83.0) Gecko/20100101 Firefox/83.0

Steps to reproduce:

• I went to a website that uses basic auth
• I entered my Username and Password after being prompted with what appears to be a new dialog for Basic Auth
• After browsing the site, I opened my dev tools and was re-prompted for my login credentials.

Actual results:

I was re-prompted for my username and password. I'd describe the Basic Auth dialog I received in this case to be the old style. From here I could either skip adding my username/password and still browse the site and use the tools, but I'd get intermittently re-prompted. Entering my username and password would keep me from getting prompted in that session.

Expected results:

I should not have been re-prompted for the username and password.

Hi Matt,

Thanks for attaching the screenshots showing the results. I tried logging into a website that uses Auth services but I was unable to reproduce the issue. By any chance do you have any test page or specific website we could use to test?

Also, please check if this issue is reproducible on the latest version of Firefox Nightly, you can download it from here: https://nightly.mozilla.org/.

Team: I'll be adding this ticket to the Core: Security component. If this is not the right component, please route it to the corresponding team if you know which one could assist us on this case.

Thanks,
Virginia

Matt, are you still experiencing this?

Hey Nicolas! Yes I'm still experiencing this. It actually went away for a short time, but it's definitely happening again. A few things I'm seeing, and I think they're all related:

• After signing in to a page/site with basic auth, I'm being re-prompted to sign in after opening the Developer tools
• After signing in to a page/site with basic auth, I'm being re-prompted to sign in after viewing the page source
• When attempting to sign into a page/site with basic auth, if I have two tabs open, the first will show the form to sign in, the second will show just a blank page with no indication it's waiting for me to sign in on the other tab

Sorry, I should have mentioned, I'm now on 85.0b6! Thanks!

Hi matt,

Any chance you can share the website where you experience this? I think this might be caused by the inspector fetching stylesheets on open, but it would be great to confirm. On the basic htaccess example webpages I could find I cannot reproduce the issue.

Thanks!

Hey Julian!

Sorry, I didn't get back to you sooner. I was out on vacation last week.

I'll see if I can set up a basic test site/page for the scenario, but a few notes in the meantime:

• The site is definitely pulling stylesheets and JS files
• The sites are also likely pulling individual files from the SASS map
• All of the stylesheets, JS, images, etc. are hosted on separate domains (a non-password-protected CDN)

I hope that helps.

Thanks!
Matthew

Going to close this as duplicate of 1696770.

It's now clear that those prompts are linked to sourcemaps resolved using the incorrect principal.
Will add more information in the other bug, but anyone impacted by this, you can work around this issue by temporarily disabling sourcemaps in the DevTools options.