Where and on what page are you trying to drop the file?

Try to drop it on empty space on the Tab Bar on on the new tab (+) button.

Thank you, cor-el.

"Try to drop it on empty space on the Tab Bar on on the new tab (+) button." That's exactly what I was trying to do.

Dragging a file (.jpg, .png, .html, .txt) into a new tab used to open - now it doesn't.

I just get a black circle with a cross through it, implying this action is now disallowed. (icon like this one, and as attached: circle-with-a-line-through-it )

I've restarted, disabled all plugins (only three), started Firefox in Safe Mode - same problem. Any ideas?

Thanks again.

Can you drop the file in the location/address bar or on an about:blank page?

I assume that it works if you use File > Open File to open the file?

Did you try to open a new window to see if it works there?

Thanks cor-el.

"Can you drop the file in the location/address bar or on an about:blank page?" No, and no.

"I assume that it works if you use File > Open File to open the file?" Yes - this works. But it's not as convenient, of course.

"Did you try to open a new window to see if it works there? " Yes - didn't work.

I should add: I reset Firefox - no change. And I can still drag files into IE or Chrome to open them - I would just prefer to keep using Firefox, as I previously have!

Thanks again. Anything else I should try?

Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.

• Download the full Firefox installer and save the file to the desktop
  https://www.mozilla.org/en-US/firefox/all.html

If possible uninstall your current Firefox version to cleanup the Windows registry and settings in security software.

• Do NOT remove "personal data" when you uninstall your current Firefox version, because this will remove all profile folders and you lose personal data like bookmarks and passwords including data in profiles created by other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

• (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
• (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

• It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.
• http://kb.mozillazine.org/Uninstalling_Firefox

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure NOT to remove personal data when you uninstall Firefox as that will remove all Firefox profile folders and you lose your personal data.

If you keep having problems then also create a new profile.

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

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

Thank you, cor-el.

I'll give reinstalling a try, and let you know how it goes.

Reinstall worked. Can now drag files (.jpg, .txt, .html) into Firefox 32.0 again to open them. Thanks again, cor-el.