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Cannot access *.localhost

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Since Firefox 89 (maybe one or two releases before) *.localhost sites are not accessible, but those sites are available through other browsers or tools (Postman, Chrome, and Edge). Localhost is an Nginx server mounted on WSL2, so it’s IP does not correspond to 127.0.0.1 which is what Firefox thinks (about:networking#dnslookuptool).

There is no Proxy enabled. I also deleted the site settings on Firefox, disabled IPv6 and prefetch with no result.

Since Firefox 89 (maybe one or two releases before) *.localhost sites are not accessible, but those sites are available through other browsers or tools (Postman, Chrome, and Edge). Localhost is an Nginx server mounted on WSL2, so it’s IP does not correspond to 127.0.0.1 which is what Firefox thinks (about:networking#dnslookuptool). There is no Proxy enabled. I also deleted the site settings on Firefox, disabled IPv6 and prefetch with no result.

All Replies (1)

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Hi Carlos, I'm not completely clear on what *.localhost means. You are using .localhost as a top level domain on your network?

If you have a lot of bandwidth and some free time, you could run a Mozregression to identify the specific patch that causes this changed behavior (for example, choose release 86 as your last known good release and 89 as your first known bad release).

More info: https://mozilla.github.io/mozregression/