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After upgrading to 20.0.1 cannot open a new window (CTRL+N) and no add-ons seem to work (apart from adblock plus).


Unable to open new window (but able to open new tabs). Sometimes unable to open Add-ons tab. The add-on extensions do not seem to be working, even though they seem to be ENABLED (except adblock plus).

When restarting in safe mode, or disabling ALL add-ons the browser works normally, thus new windows open, add-on tab opens etc.

Tried to enable one thing at a time, but it seems that when enabling WHICHEVER TWO add-ons, firefox starts acting "weirdly" (no new windows etc.).

Tried disabling hardware acceleration, but it didn't solve the problem.

Tried uninstalling firefox and then reinstalling. At first it all seemed working perfectly well: new windows opened, extensions working etc. But after a couple of restarts (of firefox and computer) it all got back to the same situation.

Tried uninstalling ALL add-ons and everything worked well. After installing the SECOND add-on and restarting firefox things get "wrong" again.

It all started after upgrading to Firefox 20.0.1.

Additional System Details

Installed Plug-ins

  • VLC media player Web Plugin 2.0.6
  • Shockwave Flash 11.7 r700
  • Next Generation Java Plug-in 10.21.2 for Mozilla browsers
  • Picasa plugin
  • GEPlugin
  • Google Update
  • iTunes Detector Plug-in
  • Adobe PDF Plug-In For Firefox and Netscape 10.1.6
  • Adobe PDF Plug-In For Firefox and Netscape 11.0.02
  • 5.1.20125.0
  • Intel web components updater - Installs and updates the Intel web components
  • Intel web components for Intel® Identity Protection Technology
  • PlayStation(R)Network Downloader Check Plug-in
  • 2.0
  • The plug-in allows you to open and edit files using Microsoft Office applications
  • Office Authorization plug-in for NPAPI browsers


  • User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:20.0) Gecko/20100101 Firefox/20.0

More Information

Tyler Downer
  • Administrator
  • Moderator
1165 solutions 6642 answers

Helpful Reply


The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

  1. Go to Firefox > Help > Troubleshooting Information.
  2. Click the "Reset Firefox" button.
  3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
  4. Firefox will open with all factory defaults applied.

Further information can be found in the Reset Firefox – easily fix most problems article.

Did this fix your problems? Please report back to us!

Thank you.

Question owner

Hello and thanks for the prompt answer.

Unfortunatelly I've already tried that (forgot to mention) and didn't solve the problem.

  • Top 10 Contributor
  • Moderator
10762 solutions 96861 answers

Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

Try a clean reinstall and delete the Firefox program folder before reinstalling a fresh copy of Firefox.

Download a fresh Firefox copy and save the file to the desktop.

Uninstall your current Firefox version, if possible, to cleanup the Windows registry and settings in security software.

  • 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.

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

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.

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

Question owner

Booting in safe mode does not make any change. It's obviously something having to do with firefox itself.

Concerning re-installing, I've already done. Actually I've tried it twice with both options: 1. keeping the "personal data" and 2. removing everything including personal data. As I've already pointed out in the original post (question) in both cases the problem seemed to have been solved (even after installing from scratch all add-ons) but after a couple of restarts the problem was again there: add-ons not actually working (apart from ad-block) and not being able to open new windows, but just new tabs

Modified by loucashornet

  • Top 10 Contributor
  • Moderator
10762 solutions 96861 answers

Did you delete the Firefox program folder before reinstalling Firefox?

You need to do this because issues with the current Firefox installation are usually caused by a broken installation that can only be cured by making sure that there are no leftover files, so you need to delete the Firefox program folder if this folder is still present after uninstalling Firefox.

onashtreelane 0 solutions 2 answers

I'm having a similar problem too. Only, when I right click Firefox will not open a new tab or open a new window. However ctrl+n does work.

I've uninstalled some add ons, and I am about to try the fixes listed.

This has been a problem since yesterday, when I updated to 20.0.1

onashtreelane 0 solutions 2 answers

Resetting seemed to fix the problem for me. Maybe it was an Add On issue. THe screen cap below is what was installed when the problem occurred.

Question owner

I've tried ALL the above referred options, including deleting program folder etc. No change at all. I've tried to find out what EXACTLY is going on, thus define better the problem.

It seems that after installing a second add-on (whichever, apart from ad-block) the problem starts. Then whenever pressing ctrl+N, or clicking the new window option, or a window tries to generate a pop-up window this does not happen. However it seems that, somehow, the "new" windows are generated but they do not appear. This means that when you close the present window the firefox process does not dissapear. It keeps running and you have to kill it in order to restart firefox. When on the other hand you click restart with all extensions disabled, then firefox shutdowns normally and restarts.

Moreover when making a clean installation of Firefox all seems to be working well. After installing the 2nd add-on things seem OK at first, but after a couple of firefox or computer restarts things get back to not normally working.

What's more peculiar is that sometimes when restarting firefox the add-on functionality as well as new window possibility come back. But after a new restart all get back to not working. Also the browser in its worst state cannot open a new tab with installed add-ons. The only way to "see" them and disable uninstall some of them is restarting firefox with add-ons disabled.

All these describe the problem. Any help could be usefull, because I can not decently use firefox anymore. I am, somewhat, addicted to the use of a couple of add-ons and I cannot use any of them (apart from adblock!!!). The only solution seems to be switching to another browser, which I do not want to do!