Does this happen on many websites, some, a few?

Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

Note that on Mac we recently have seen a lot of crash reports about the fbplugin (Facebook photo uploader) in the "Internet Plug-Ins" folder (#1502977), so maybe check for the presence of this plugin.

• [/questions/1238157] Firefox crashes because of the fbplugin plugin

FredMcD said

Does this happen on many websites, some, a few? Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there? https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

It crashes on all sites.

cor-el said

Note that on Mac we recently have seen a lot of crash reports about the fbplugin (Facebook photo uploader) in the "Internet Plug-Ins" folder (#1502977), so maybe check for the presence of this plugin.

• [/questions/1238157] Firefox crashes because of the fbplugin plugin

As I mentioned, I'm running it without any plugins installed.

Let’s do a full clean re-install;

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)

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

FredMcD said

Let’s do a full clean re-install; 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) 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

I did that a couple of times and it still crashes silently, and generates no warning...so I need to access some debug logs, otherwise I'll never find the root cause.

Did you try Firefox Safe Mode?

FredMcD said

Did you try Firefox Safe Mode?

I did and it seems to be a lot more stable, but as far as I can tell, it just disables the themes as I did not install any other plugins...weird.

https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes). If the problem goes away, that tells us one thing. If it does not, that tells us something else.

Did you at least check the Mac "Internet Plug-Ins" folder?

This fbplugin plugin doesn't show in "Add-ons -> Plugins", but appears to make Firefox crash when it scans this folder for finding plugins.

• /Library/Internet Plug-Ins
• ~/Library/Internet Plug-Ins

If you have submitted crash reports then please post the IDs of one or more recent crash reports that start with "bp-".

• bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

You can find the report ID of recent crash reports on the "Help -> Troubleshooting Information" (about:support) page.

• click the "All Crash Reports" button on this page to open the about:crashes page and see all crash reports.

Alternatively you can open about:crashes via the location/address bar.

See also:

• https://support.mozilla.org/en-US/kb/Mozilla+Crash+Reporter

I would like to thank everyone for their help in this matter. I was not able to find the root cause for those constant crashes but it seems that Firefox 65 is stable again (at last on this Macbook unit).

Hopefully it will remain that way for good :)

Cheers.

As long as the problem is gone. Please flag your last post as Solved Problem so others will know.