I am not too sure I correctly understand your description. _{(You are not talking about restarting Firefox, and having blank tabs instead of the expected tabs from the last session, or home tabs are you ?)}

Lets make an educated guess, and say whatever you see may be down to the addons. Try in safe mode does the problem go away ?

• Diagnose Firefox issues using Troubleshoot Mode
• Disable or remove Add-ons

Next try in the ordinary mode starting with all extensions disabled. Then test after enabling the extensions one at a time. You may need to restart after some are re-enabled.

Are you able to narrow down the problem to use of one or a combination of addons.

This is not when I open Firefox. It's when I'm already in it. A typical scenario: I use Firefox one day. Quit and the next day, all my tabs show up. However, if I click on one, it immediately goes to a "New Tab."

Here's what I'm suspecting: I turned on Private Browsing by turning on "Use Tracking Protection in Private Windows, but it was just for one site. I also turned on "Do Not Track." Could this be the cause?

That being said, I turned both off in preferences, quit and restarted. But it's still happening.

I guess from what you say that it is not very predictable.

If it happens more frequently or you are able to find some way of forcing the fault we may make progress.

You could try a clean install. That involves removing the program files before reinstalling Firefox. Just take care and only delete the program files not the profile files. That may help but I have no specific evidence it will resolve your problem.

Clean Install

Certain Firefox problems can be solved by performing a Clean reinstall. This means you remove your Firefox program files and then reinstall Firefox. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location.

To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.

1. Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (or open the Firefox menu and click the close button ).
3. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • Windows:
     • C:\Program Files\Mozilla Firefox
     • C:\Program Files (x86)\Mozilla Firefox
   • Mac: Delete Firefox from the Applications folder.
   • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
4. Now, go ahead and reinstall Firefox:
   1. Double-click the downloaded installation file and go through the steps of the installation wizard.
   2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

More information about reinstalling Firefox can be found here.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.

Did you try Safe Mode?

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

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

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

Okay, I think I solved the issue. It was because I turned on "Use Tracking Protection..." and "Do Not Track" that this issue started to happen. It may be just the "Use Tracking Protection" option that did it. I had to constantly sign on to sites, etc. So I think this has been solved. Thanks cor-el and John99 for your help.