mxyzptlk13 said

then i deleted all visible and invisible files connected to app

Let’s do a full clean re-install;

Note: Firefox comes in three or more folders on all computers. They are;

Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user.

If you remove the Firefox folder, the user profiles would not be affected.

Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Note: Check Both Folders

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove any profile folders.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select Network.

[v56+] Type about:preferences#general<enter> in the address bar. Look for Network. +++++++++++++++++++++ Look for Configure How Firefox Connects and press the Settings button. If you are using a proxy, make sure those settings are correct. If there is no proxy, first try No Proxy. If there is a problem, then try System Proxy.

Some problems occur when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again;

• Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
• Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see

Configure firewalls so that Firefox can access the Internet {web link}

i've been in the desktop computer game since my Macintosh 128K in 1984, prior to that i was taking fortan/basic/cobol classes in college while i was still in high school in the late 60s.

I appreciate your solution, but it hinges on the assumption that I don't know what I'm doing. I run state-of-the-art software, including CleanMyMac 4.4.0.2, i have a 3,46GHz 12-core MacPro with 32Gbs ram, and an SSD boot drive. my firewall is configured to "Automatically allow downloaded signed software to receive incoming connections." No testing or software revealed any issues whatsoever.

"Most of what you'd written ignored "I dl'd FF developer and it ran perfectly out of the box. safari and chrome work also. i then checked/compared all the NETWORK, CONNECTION, and PROXY SETTINGS, and they MATCH FF developer EXACTLY." So basically you suggested was what I'd already tried. Out of respect, I rechecked every single item you mentioned before writing any sort of reply because all the experience in world doesn't make one infallible. btw, this issue started about 10 days after successfully upgrading and using FF 66.0.3.

Bottom line – I would never have posted the problem if I hadn't exhausted every possible solution that 50+ years of experience brings to the table. i should have shared my qualifications in my original post, but after the 3 attempts that wouldn't let me post, i only gave attempt #4 a 20% success rate. if necessary, i can probably use FF-developer for my needs, although i would have told my students that relying on alpha or beta versions for professional work is not advised. Up until now, the worst FF problem I've ever had was trying to believe "FireFox will Never remember history." However there are Add-Ons to solve that problem instantly.

The was one more reason why I posted the problem... I can't think of any hell on earth worse than trying to spend all my time working and playing in safari or chrome <shiver>. i started using Phoenix in about 2003, and have been a loyal FF user since then.

My first response is in case you removed the wrong files. This would also reset some program data.

My second response is the normal things to check when a program is not able to connect to the web.