Does your home page use Flash? Otherwise, it's hard to think of a reason for plugin-container to be running. Anyway, I suspect that is a red herring and we really need to figure out what is broken with your Firefox.

Could you try starting in Firefox's Safe Mode? That's a standard diagnostic tool to deactivate extensions and some advanced features of Firefox. More info: Diagnose Firefox issues using Troubleshoot Mode.

If Firefox is not running: Hold down the Shift key when starting Firefox.

If Firefox is running: You can restart Firefox in Safe Mode using either:

• "3-bar" menu button > "?" button > Restart with Add-ons Disabled
• Help menu > Restart with Add-ons Disabled

and OK the restart.

Both scenarios: A small dialog should appear. Click "Start in Safe Mode" (not Refresh).

Can you use Firefox in this mode?

Also, do you get the Mozilla Crash Reporter dialog for the Firefox crash? If so, your Firefox may have logged some data that would help track down the cause of the problem. You can submit that data to Mozilla and share it with forum volunteers to see whether it points to the solution. Please check the last section of the support article "Firefox Crashes" for steps to get those crash report IDs from the about:crashes page (or from disk if necessary), and then post some of the recent IDs here.

I've tried that as well. Same deal in safe mode; it simply doesn't work if I click anything. Also, my homepage is a prompt to allow Firefox to use my ActivClient CAC reader via Firefox. Don't know if that makes a difference or not.

Could you try starting Firefox to a blank page: in the Start menu search box, type or paste the following and press Enter:

firefox.exe "about:blank"

Of course, Firefox might then try to do a crash recovery... or it might prompt you for your credentials anyway.

That does successfully bring up a blank tab, but I still can't click anything without it crashing.

Could you do this three-minute experiment:

Create a new Firefox profile

A new profile will have your system-installed plugins (e.g., Flash) and extensions (e.g., security suite toolbars), but no themes, other extensions, or other customizations. It also should have completely fresh settings databases and a fresh cache folder.

Exit Firefox and start up in the Profile Manager using Start > search box (or Run):

firefox.exe -P

Don't delete anything here!

Any time you want to switch profiles, exit Firefox and return to this dialog.

Click the Create Profile button, assign a name like TEST081115, and skip the option to relocate the profile folder. After creating the profile, select it and start Firefox in that profile.

Can you click without freezing Firefox? If so, could you take a census of your active plugins using this page and post the list back: https://jeffersonscher.com/res/plugins.html

When returning to the Profile Manager, you might be tempted to use the Delete Profile button. But... it's a bit too easy to accidentally delete your "real" profile, so I recommend resisting the temptation. If you do want to clean up later, I suggest making a backup of all your profiles first in case something were to go wrong.

If you want to test this profile out a little more, you can restore a bookmark backup from your regular profile. Restore bookmarks from backup or move them to another computer. The file is a little tricky to locate, but when you open the dialog to choose the file, you can get close to your regular profile folder by pasting the following in the file name and pressing Enter:

%APPDATA%\Mozilla\Firefox\Profiles

You'll see the one you just created (TEST). It's the other one or one of the other ones, if there are several.

Wow! That did the trick; so I assume I can simply create a new profile and use it as my primary from now on?

Here are the plug-ins. Never realized I had so many, but looking through them I've used them all fairly regularly:

• Name (Version): Wacom Dynamic Link Library (1.1.0.9)
  Description: Wacom Dynamic Link Library
  File name: npwacom.dll
• Name (Version): Adobe Acrobat (11.0.12.18)
  Description: Adobe PDF Plug-In For Firefox and Netscape 11.0.12
  File name: nppdf32.dll
• Name (Version): AdobeAAMDetect (1.0.0.0)
  Description: A plugin to detect whether the Adobe Application Manager is installed on this machine.
  File name: npAdobeAAMDetect32.dll
• Name (Version): DBsign Government Smart Card Information Tool (3.0.0.119)
  Description: The DBsign Government Smart Card Information Tool allows data elements from GSC compliant smartcards to be read from browser based applications. USE OF THIS PRODUCT IS GOVERNED BY THE DBSIGN LICENSE AGREEMENT.
  File name: npDbsGscInfo.dll
• Name (Version): DBsign Web Signer (3.0.0.119)
  Description: DBsign Web Signer Plugin
  File name: npDBsignWeb.dll
• Name (Version): Google Earth Plugin (7.1.5.1557)
  Description: GEPlugin
  File name: npgeplugin.dll
• Name (Version): Google Update (1.3.28.1)
  Description: Google Update
  File name: npGoogleUpdate3.dll
• Name (Version): Intel® Identity Protection Technology (2.0.59.0)
  Description: Intel web components for Intel® Identity Protection Technology
  File name: npIntelWebAPIIPT.dll
• Name (Version): Intel® Identity Protection Technology (2.0.59.0)
  Description: Intel web components updater - Installs and updates the Intel web components
  File name: npIntelWebAPIUpdater.dll
• Name (Version): iTunes Application Detector (1.0.1.1)
  Description: iTunes Detector Plug-in
  File name: npitunes.dll
• Name (Version): Java Deployment Toolkit 7.0.790.15 (10.79.2.15)
  Description: NPRuntime Script Plug-in Library for Java(TM) Deploy
  File name: npdeployJava1.dll
• Name (Version): Java(TM) Platform SE 7 U79 (10.79.2.15)
  Description: Next Generation Java Plug-in 10.79.2 for Mozilla browsers
  File name: npjp2.dll
• Name (Version): Nitro PDF plugin for Firefox and Chrome (3.5.2.10)
  Description: Nitro PDF plugin for Firefox and Chrome
  File name: npnitromozilla.dll
• Name (Version): NVIDIA 3D Vision (7.17.13.1100)
  Description: NVIDIA 3D Vision plugin for Mozilla browsers
  File name: npnv3dv.dll
• Name (Version): NVIDIA 3D VISION (7.17.13.1100)
  Description: NVIDIA 3D Vision Streaming plugin for Mozilla browsers
  File name: npnv3dvstreaming.dll
• Name (Version): Shockwave Flash (18.0.0.232)
  Description: Shockwave Flash 18.0 r0
  File name: NPSWF32_18_0_0_232.dll
• Name (Version): Shockwave for Director (12.1.9.160)
  Description: Adobe Shockwave for Director Netscape plug-in, version 12.1.9.160
  File name: np32dsw_1219160.dll
• Name (Version): Silverlight Plug-In (5.1.40416.0)
  Description: 5.1.40416.0
  File name: npctrl.dll
• Name (Version): VLC Web Plugin (2.2.1.0)
  Description: VLC media player Web Plugin
  File name: npvlc.dll
• Name (Version): Wolfram Mathematica (9.0.61.60027)
  Description: Enables the interaction of Mathematica content with the latest installed version of Mathematica.
  File name: npmathplugin.dll

Okay, well, the good news is, a clean profile works. The reason to look at plugins is whether any are known to create UI issues. None look problematic to me in a quick read.

As the next test, could you re-enter your ActivClient CAC credentials and see whether Firefox is still stable in the new profile?

It seems to work fine with ActivClient as well.

Okay, you can try copying over important files, for example, if you want your history, that is combined with bookmarks in the places.sqlite database file. Saved passwords... This article goes through it in detail: Recovering important data from an old profile.