Try these things first;

Start Firefox in Safe Mode {web link} While you are in safe mode; Press the Alt or F10 key to bring up the tool bar. Followed by;

Windows; Tools > Options Linux; Edit > Preferences Mac; application name > Preferences

Then Advanced > General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.

It could be the work of one of your add-ons, or even add / mal-ware. Look thru your add-ons list and make sure you know what each one is and what it does. Also, check the programs that are on your computer

Windows: Start > Control Panel > Uninstall Programs. Mac: Open the "Applications" folder Linux:

• Ubuntu Unity {web link}
• Xfce: Applications Menu category sections
• options depends on the package manager and the desktop environment

Go thru the list. If you find something that you don't know what it is, use a web search.

Troubleshoot Firefox Issues Caused By Malware {web link}

We have seen reports about a Community Toolbar extension causing this issue with not being able to open a new tab. So if you have any shown in Firefox/Tools > Add-ons > Extensions then start there.

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

My add-ons are:

AdBlock Plus 2.6.4 Add To Amazon Wish List 1.10 DivX Plus Web player HTML5 2.1.2.145 DownloadHelper 4.9.22 Flash And Video Download 1.59 TinEye Reverse Image Search 1.1 Vuze Community Toolbar 3.21.0.1

Themes The Police "Let's Eat!' (disabled)

Plug-Ins 1.0 (turns out its facebook) DivX Plus web player 2.2 DivX VOD helper 1.1 Flip4Mac WinMedia plugin 3.1.0.1 iPhotoPhotocast 6.0 Java Applet 14.9.0 Quicktime 7.71 Shockwave Flash 14.0.0.145 Silverlight 5.1.30317.0 Wacom Pressure Plug-in 2.1.0-1 Wacom Tablet Plugin 2.1.0.2

I noticed last night that while I can't get anything to happen by drop-down menu nor by clicking the little star on the toolbar, I can get another tab to open if I click on anywhere in the generic area of the toolbar. This only works for so long, though... until you get about 5 or 6 tabs in the window, then clicking on it causes it to minimize to the dock. So you have to open a new window and start again.

You can try to disable the Vuze Community Toolbar 3.21.0.1 extension that shows in the list as that is the most likely candidate for causing this issue.

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

I simply deleted it altogether. Still no difference.

Does it work in Firefox Safe Mode?

Yes, it worked in Safe Mode.

Rather than go disabling one-by-one through the plug-ins and such, I decided to delete some stuff. It appears, at this point, that the Facebook plug-in - which was installed without asking, naturally - was the culprit. I've been off Facebook since January so this was no big loss to me at all. I also meant to mention that the other, major thing I removed was the iPhoto Photocast thing. Whatever that was, I have no idea and I've obviously never used it.

I'm just glad to have Firefox back, so I can ditch Chrome. Thanks for everyone's help!

Hello,

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution more easily.

Thank you for contacting Mozilla Support.