Unfortunately, that's being caused by the TorButton addon.

You have to disable it to fix this. Go to Tools > Add-ons then Extensions and click on TorButton, choose Disable. Then close Firefox and reopen it.

FYI: This was due to a sloppy fix by Mozilla for a crash bug. Rather than merging a proper fix for the issue, they elected to break Drag and Drop for all Torbutton users instead. Pretty amazing.

I can't fix this from Torbutton. See https://bugzilla.mozilla.org/show_bug.cgi?id=715885#c33 for why.

The Tor Project recommends people use Tor Browser instead of Firefox + Torbutton anyway, because it provides major privacy improvements over normal Firefox that also aren't possible without patches. See https://www.torproject.org/projects/torbrowser/design/#privacy for the improvements.

You can get it at https://www.torproject.org/download/download-easy.html

Oh, awesome! An actual reply from Mike Perry (one of the makers of TorButton) himself!

Thanks for replying Mike and breaking down what happened. I google searched and found the bug you fixed for this issue last year on TorButton's Github page. And I wondered why it was still broken. Then I found another thread about Torbutton on this site where it was mentioned that b/c of a Firefox bug fix TorButton's drag-n-dropping was busted.

I was going to add some of that extra info here, but when I tried to visit the bug link, Bugzilla was down. Anyway, thanks for commenting & letting TorButton users know about the other alternative, Tor Browser.

FYI, downthemall! 2.0.13 is causing the same problem for me.

Ok, what if you don't have the tor button as an extension? Used to be able to move tabs around then, poof! I could not move them, in mid-session. Been trying to fix, but to no avail.

Start Firefox in Safe Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance/Themes).

• Don't make any changes on the Safe mode start window.
• https://support.mozilla.org/kb/Safe+Mode

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

Before I got message you had responded, I went into troubleshooting and just reset firefox, which drops all the extensions I had on (did screen shots of extension and theme bars first, so I can go back and get the ones I use most.

STILL can't move anything. Furthermore, now I can't drag anything on my Thunderbird email either. Can't drag items to files, so back to all that #@)(!#$(@# clicking and menus. Will try safe mode tomorrow, when patience might have returned.

You can also do a clean reinstall and delete the Firefox program folder (C:\Program Files\Mozilla Firefox\) before reinstalling a new copy of Firefox.

You can find the latest Firefox release in all languages and for all Operating Systems here:

• Firefox 14.0.x: http://www.mozilla.org/en-US/firefox/all.html

• Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will also lose your personal data like bookmarks and passwords from profiles of other Firefox versions.

Your bookmarks and other profile data are stored in the Firefox Profile Folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.

• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/Profile_backup

• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall

Appreciate your assist. Already had Firefox 14 on my machine. Frankly, am wondering if THAT isn't the problem. Problems started up slowly and shortly after Firefox and Thunderbird both updated to new make.

Am really at wits end. I wondered if the new IE browser might be the problem so that got uninstalled yesterday. Didn't help a bit. I hate MS programs but have to use IE at a couple of sites I have to use occasionally.

If there are Thunderbird and Firefox versions installed that use different versions of the same URL then it can make a difference if Thunderbird has already been started and a possibly older version of a DLL is still or already loaded.

Does it work better if you haven't started Thunderbird since rebooting the computer?

Gads, you have the patience of a saint. Does not work better no matter when I start Thunderbird.

To top that off, now I can't click and drag ANYTHING, which is a problem since I have to reconfigure Firefox since I reset it. Now I can't even customize the tool bar, can't move buttons, nada, zip.

Beginning to think the Kapersky anti-virus/protection program my spouse bought and I have hated has let in some bad waddies. I want my vipre back! LOL Computer has been cranky ever since Kapersky has been on, and getting worse all the time.

Still thinking things were much better before the latest firefox and thunderbird makes. Do I need to remove those programs and go to an older version? Will I lose all my mail files?

Thanks for your help You have really been a champ, but nothing seems to be working, things keep getting worse. Machine may fly out window any minute now....