Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is is causing the problem.

• switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
• do NOT click the "Refresh Firefox" button on the Safe Mode start window

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

It is possible that your firewall or other security software blocks or restricts Firefox without informing you, possibly after detecting changes (update) to the Firefox application. Remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full, unrestricted, access for Firefox and the plugin-container process and the updater process.

See:

• https://support.mozilla.org/en-US/kb/server-not-found-connection-problem
• https://support.mozilla.org/en-US/kb/Firewalls
• https://support.mozilla.org/en-US/kb/fix-problems-connecting-websites-after-updating

RangerDan said

Since downloading latest FF. When I click on most links, the new Tab opens to a blank page. Works fine with all other browsers. Also when opening a Bookmark, Tab only shows the links Index of contents yet when I use another browser, it opens to contents immediately...

You don't happen to have the FDM (Free Download Manager) or other download Manager Extension, do you?

~Pj

No...Worked fine until latest Download.

cor-el said

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is is causing the problem.

• switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
• do NOT click the "Refresh Firefox" button on the Safe Mode start window

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode
• https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

---

It is possible that your firewall or other security software blocks or restricts Firefox without informing you, possibly after detecting changes (update) to the Firefox application. Remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full, unrestricted, access for Firefox and the plugin-container process and the updater process.

See:

• https://support.mozilla.org/en-US/kb/server-not-found-connection-problem
• https://support.mozilla.org/en-US/kb/Firewalls
• https://support.mozilla.org/en-US/kb/fix-problems-connecting-websites-after-updating

After working all day on this, your suggestions not only do NOT work BUT returning FF to "Default" brought MANY different problems!!! 1) URL links open to a page that list Contents of the Page only but do NOT open the link addressed. To clarify..I have a military website that shows all yearbooks for certain units. The URL points to a specific units yearbook and in IE, Safari, Chrome, Edge they all open to that exact page and the yearbook. FF now only opens to the Index of all categories on the website but doesNOT allow you to open individual pages showing yearbooks. 2) certain URL's are loaded into the "Library" icon in the right top of FF page. Then you have to click on that downloaded entry to go to the downloaded page but it is just that, a downloaded page..you still do NOT access the entire website.

Just plain absurd!!!!