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Firefox Dev can’t establish a connection to local server

  • 4 replies
  • 15 have this problem
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  • Last reply by Alan W

Alan W
Alan W
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I'm a web developer that setup a local environment under Linux Mint.

For some reason, Firefox Developer Edition (59.0b7 64-bit) cannot access sites on my localhost. The interesting thing is that Firefox Quantum 58.0.1 (64-bit) is showing these local sites perfectly fine. I've tested other browsers, including Konqueror and Lynx, and these work fine also.

I've setup my environment so that apache2 can serve pages from a 'wildcard' virtual host. Using symlinks, I can link my project files to another directory that functions as the web root. Thus:

/home/me/business/projects/client/index.html => /home/me/business/www/client/index.html

Navigating to http://client.dev brings up the page perfectly in Firefox 58, Konqueror, and Lynx.

However, Firefox Developer Edition, AND Google Chrome, both fail to load the page. The URL changes from http://client.dev to https://client.dev and throws this message:

"Unable to connect

Firefox can’t establish a connection to the server at client.dev."

I've played around with the about:config settings for Network.dns.* but nothing seems to help. Also, the apache logs do not produce anything useful.

Your input will be greatly appreciated.

I'm a web developer that setup a local environment under Linux Mint. For some reason, Firefox Developer Edition (59.0b7 64-bit) cannot access sites on my localhost. The interesting thing is that Firefox Quantum 58.0.1 (64-bit) is showing these local sites perfectly fine. I've tested other browsers, including Konqueror and Lynx, and these work fine also. I've setup my environment so that apache2 can serve pages from a 'wildcard' virtual host. Using symlinks, I can link my project files to another directory that functions as the web root. Thus: /home/me/business/projects/client/index.html => /home/me/business/www/client/index.html Navigating to http://client.dev brings up the page perfectly in Firefox 58, Konqueror, and Lynx. However, Firefox Developer Edition, AND Google Chrome, both fail to load the page. The URL changes from http://client.dev to https://client.dev and throws this message: "Unable to connect Firefox can’t establish a connection to the server at client.dev." I've played around with the about:config settings for Network.dns.* but nothing seems to help. Also, the apache logs do not produce anything useful. Your input will be greatly appreciated.

Chosen solution

Here's a solution to disable HSTS:

1) about:config

2) Right-click: New Integer

3) Name: test.currentTimeOffsetSeconds

4) Value: 11491200

5) Clear all history, all time

Disable HSTS

Read this answer in context 👍 4

All Replies (4)

©TriMoon™
©TriMoon™
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Could it have to do with HSTS ?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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See:

  • /questions/1204477 Localhost: This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox Developer Edition may only connect to it securely. As a result, it is no

Modified by cor-el

Alan W
Alan W Question owner
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Bingo!

Downloading Firefox 59.0b1 worked, and I was able to see my localhost sites. However, the automatic update to 0b9 screwed things all over again.

Thank you TriMoon and Cor-el.

Alan W
Alan W Question owner
more options

Chosen Solution

Here's a solution to disable HSTS:

1) about:config

2) Right-click: New Integer

3) Name: test.currentTimeOffsetSeconds

4) Value: 11491200

5) Clear all history, all time

Disable HSTS