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Firefox freezers site and shut down of my Mac PC.

  • 1 reply
  • 1 has this problem
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  • Last reply by FredMcD

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I recently had a Black 3TB internal OS Hard Drive installed in my 27in Mac Computer by an Apple associated store. They also transferred my Application Data across from my old Hard Drive to the new one as part of the service. Whilst Catalina interfered with many of my apps, as Catalina is a 64BIT processor, I have overcome many of the problems associated with this new OS installation. The company updated my OS system to Catalina in the process of transferring the Data, and although I never thought at the time that this would occur, so did not mention to them that I wanted to stay with Mojave. But now I have Catalina installed and upgraded all my apps that would not open after installation, to 64Bit including Firefox, but my browser keeps freezing up when using it after a while and stops shutting down when I try to restart my PC to unfreeze Firefox. this is quite annoying as I wish to continue with Firefox as my Web Browser, as I use the LastPass app for my Log In to each site and this is not possible with Safari or Google, can you advise me regarding a solution to this problem as I have deleted Firefox several times and downloaded a new one many times but this does not fix the problem. Regards Brian Shaw.

I recently had a Black 3TB internal OS Hard Drive installed in my 27in Mac Computer by an Apple associated store. They also transferred my Application Data across from my old Hard Drive to the new one as part of the service. Whilst Catalina interfered with many of my apps, as Catalina is a 64BIT processor, I have overcome many of the problems associated with this new OS installation. The company updated my OS system to Catalina in the process of transferring the Data, and although I never thought at the time that this would occur, so did not mention to them that I wanted to stay with Mojave. But now I have Catalina installed and upgraded all my apps that would not open after installation, to 64Bit including Firefox, but my browser keeps freezing up when using it after a while and stops shutting down when I try to restart my PC to unfreeze Firefox. this is quite annoying as I wish to continue with Firefox as my Web Browser, as I use the LastPass app for my Log In to each site and this is not possible with Safari or Google, can you advise me regarding a solution to this problem as I have deleted Firefox several times and downloaded a new one many times but this does not fix the problem. Regards Brian Shaw.

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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