It could be the work of one of your add-ons, or it could be Hardware Acceleration. How to disable Hardware Acceleration {web link}

Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control> (Mac=<Command>) <Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All Of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is, detective.

So, I turned off hardware acceleration, and tried disabling all extensions except for ublock. Still couldn't get the menu with ublock. Then I disabled ublock and enabled multple tabs handler. Still couldn't get the popup menu with that. I restarted between each change and trying to use the menu.

I called for more help.

Start your Computer in safe mode with network support. Then start Firefox. Try Safe websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

Problem still persists in safe mode.

Have you tried disabling Hardware Acceleration. How to disable Hardware Acceleration {web link}

Yes, I did. I even tried disabling that along with the toggling of addons as stated earlier.

I'm a "me too" here. Disabled every extension except Ublock (adblock+ does the same and other addons as well).

Removed my Chrome/userChrome.css file (this created some curved tabs and enlarged menus). No change.

Disabled hardware accel. No change.

And, yes, I have restarted FF after each try.

I've run FF as a different user and it works just fine.

I'm starting to think that it must be a setting in about:config ?? No idea how i'd track that down?

Hi Mellobob, could you check for error message in the "Browser Console" that could be related to this problem.

You can open the separate Browser Console window using either:

• "3-bar" menu button > Web Developer > Browser Console
• (menu bar) Tools > Web Developer > Browser Console
• (Windows) Ctrl+Shift+j

Click the trash can icon at the upper left to clear the window, then switch back over to your main window and try one of the buttons that has a broken drop-down (technically called a popup in extension-speak).

Then switch back over to the console window. Did Firefox log any errors related to the toolbar button action?

More info on the Browser Console: https://developer.mozilla.org/docs/Tools/Browser_Console

jscher2000 said

Hi Mellobob, could you check for error message in the "Browser Console" that could be related to this problem. You can open the separate Browser Console window using either:

• "3-bar" menu button > Web Developer > Browser Console
• (menu bar) Tools > Web Developer > Browser Console
• (Windows) Ctrl+Shift+j

Click the trash can icon at the upper left to clear the window, then switch back over to your main window and try one of the buttons that has a broken drop-down (technically called a popup in extension-speak). Then switch back over to the console window. Did Firefox log any errors related to the toolbar button action? More info on the Browser Console: https://developer.mozilla.org/docs/Tools/Browser_Console

Thanks for this suggestion. I just tried it ... no errors or warnings listed.

I have "solved" the issue by creating a new profile. Fortunately the "Refresh Firefox" option makes this mostly painfree. Still, it is a pain.

I'm keeping the old profile around for now to test any other suggestions.

Hey Mellobob, I've still yet to resolve my issue. By new profile, do you mean like a new firefox profile? A new user on your Windows PC?

Also, I didn't get any errors listed with the pop-up menus, jsher.

Not a new user on the computer. A new Firefox profile for the same user.

I followed the instructions here:

link text

It would be nice, BTW, to have this process a bit easier to find :)