Diễn đàn hỗ trợ Firefox

NOTE: I have marked this as "Solved" because I figured out the problem described below, and I fixed it. See my following message here for a description of my solution.

Original message starts here ...

I'm using Firefox 144.0 under Debian Linux. I've used Firefox on this machine for years with no problem. Firefox can easily connect to literally thousands of web servers on the internet, both via HTTP and HTTPS.

But now, I'm having an issue:

I started running a web server on the same machine that Firefox is running on. This server only listens for non-HTTPS connections on port 80. I am not using any proxy server with Firefox.

I can easily and directly connect to my local web server's pages from my local machine from Chrome, w3m, curl, and direct telnet connections to port 80 ... all of which are addressing the publicly accessible domain name for my local web server. However, However, Firefox refuses to connect to any URL's on my local machine, and it gives me the following explanation:

Unable to connect

Firefox can’t establish a connection to the server at [ my server's domain name ].

   The site could be temporarily unavailable or too busy. Try again in a few moments.
   If you are unable to load any pages, check your computer’s network connection.
   If your computer or network is protected by a firewall or proxy, make sure that Firefox is permitted to access the web.

In Firefox, I have all auto-forcing of HTTPS disabled by means of Don’t enable HTTPS-Only Mode turned on.

I get the same error in Firefox whether I connect via a URL like "http://MYFULLDOMAINNAME" or a URL like "http://AAA.BBB.CCC.DDD", where "AAA.BBB.CCC.DDD" is my machine's publicly accessible static IP address and "MYFULLDOMAINNAME" is the long-standing, publicly accessible domain name for my machine ... both with and without a suffix of ":80" on the supplied URL.

And again, all other browsers on my machine have no problem whatsoever connecting to my own local web server on this same local machine of mine using those same URL's.

And all browsers (Firefox and otherwise) that are running on other machines all over the internet have no problem connecting to that same web server via the same URL's that I described above

Also, I have no firewall rules on my machine which would block access to my own machine's port 80.

What could be causing this error in Firefox, and what might I be able to do to fix it?

Thank you very much in advance.

UPDATE: Just a bit more information. Looking at the web logs, I see that Firefox's request never even reaches my local web server. In other words, Firefox itself is not even trying to make a TCPIP port 80 connection to my local web server in the first place

Yesterday, the Firefox quit working. Today my connection was verified by Fios and during the phone call, we tried Google Chrome (Yuck!) and it worked on the internet. I have downloaded the latest Firefox and it still does not work. Is there a problem with Firefox? Should I delete Firefox and reinstall?

I keep getting the same DNS error for pages that I have been to 100s of times before. Why is this happening now? I'm guessing it's because of a recent update, but can't imagine why Firefox has an issue with Rebel Sport all of a sudden.

Have attached a copy of the error page. Hoping someone can explain why this is happening and how to get rid of it.

I have a secure private network on my CPU. Why does Firefox not allow my secure websites to remember this browser? The website gives me the option "Recognize this browser." I check that box. But it is a vicious cycle. There is such a thing as too much protection. This makes it time consuming to access my accounts, requiring a cell phone and code to access accounts. Please advise.

For the last day I've been having a problem with FF slow to load. I've tried the troubleshoot mode with little change. When it does load I can have problems with certain web sites loading e.g. Youtube, MSNBC, AOL mail etc. It's never consistent. The cache is clean and I've saved all the relevant cookies, I checked my internet provider and they are having no problems and I don't seem to be having any internal hdw issues e.g. ethernet cable connections etc. I reinstalled FF-not a clean install and seemed to help for a time. Do I have any options other than a refresh? I don't seem to be having the same issues with Edge or Chrome. All W11 updates are current. I look forward to anyone's comments.

I had 128.7 esr installed and was getting crashes and upgraded to 128.8 esr and it was worse. Down graded to 128.0 esr and it seems to be working just fine so I will not be doing any further upgrades.

when i open this website, it shows like this: https://in.tradingview.com/

Secure Connection Failed

An error occurred during a connection to in.tradingview.com. The OCSP response is not yet valid (contains a date in the future).

Error code: SEC_ERROR_OCSP_FUTURE_RESPONSE

   The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
   Please contact the website owners to inform them of this problem.