Firefox repeatedly opens empty tabs or windows after you click on a link

Revision Information
  • Revision id: 170534
  • Created:
  • Creator: AliceWyman
  • Comment: reworded note on problematic PDF files
  • Reviewed: Yes
  • Reviewed:
  • Reviewed by: AliceWyman
  • Is approved? Yes
  • Is current revision? No
  • Ready for localization: Yes
  • Readied for localization:
  • Readied for localization by: AliceWyman
Revision Source
Revision Content

Firefox may repeatedly open new, empty tabs or windows after you click on a link, forcing you to close Firefox. The same untitled tabs or blank windows may open the next time you start Firefox if the previous session is restored.

This usually happens because you chose Firefox as the program to always use for a particular action, such as opening a certain type of file or launching an application to send mail.

Note: The Refresh Firefox feature can fix many issues by restoring Firefox to its default state while saving your essential information. Consider using it before going through a lengthy troubleshooting process.

Start a new Firefox session

You may be forced to close Firefox if it is repeatedly opening multiple tabs or windows. Firefox includes a Session Restore feature that can restore your windows and tabs from the previous session after a crash or unexpected close.

The same multiple tabs or windows may start opening when you next start Firefox, forcing you to close Firefox again. If you see a Restore Session ( "Well, this is embarrassing.""Sorry. We're having trouble getting your pages back.") page when you restart Firefox, click the CloseStart New Session button to start a new session and then follow the instructions given below to fix the problem.

Change the action for a content type

You may be able to fix the problem by finding the content type that is set to use Firefox and then changing the action, using these steps:

  1. In the Menu bar at the top of the screen, click Firefox and then select Preferences or Settings, depending on your macOS version.Click the menu button Fx89menuButton and select Settings.
  2. Select the Applications panel.In the General panel, go to the Applications section.
  3. If you know which item in the Content Type column is causing the problem, select it. Otherwise, in the Search box, type Use Firefox. The list will display only items that are set to "Use Firefox".
    Applications - Use Firefox 38Fx56GeneralApplications-UseFirefoxapplications setting 57Fx61ApplicationsUseFirefox
  4. Select each problematic content type and choose a new action from the drop-down menu in the Action column. If you're not sure which action to pick, choose Always ask.
    • Note: A problematic Portable Document Format (PDF) content type should be set to Preview in Firefox to view PDF files in Firefox, even when Firefox is the default program to open PDF files on Windows.
  5. Close the Settings page. Any changes you've made will automatically be saved.

For general information about content types, see Manage file types and download actions in Firefox.

Reset actions for all content types

If the preceding steps didn't fix the problem, or if you can't find the problematic item in the Applications list, you will have to reset the actions for all content types by manually deleting the file that stores these settings.

This will remove all customized content type actions, not just the one that is causing the problem. You will have to make those changes over again after taking these steps.

  1. Open your profile folder:

    • Click the menu button Fx89menuButton, click Help and select More Troubleshooting Information.From the Help menu, select More Troubleshooting Information. The Troubleshooting Information tab will open.
    • Under the Application Basics section next to Profile FolderDirectory, click Open FolderShow in FinderOpen Directory. A window will open that contains your profile folder.Your profile folder will open.
    Note: If you are unable to open or use Firefox, follow the instructions in Finding your profile without opening Firefox.

  2. Close Firefox. Click the Firefox menu Fx89menuButton and select Exit.Click the Firefox menu at the top of the screen and select Quit Firefox.Click the Firefox menu Fx89menuButton and select Quit.
  3. Delete the file named mimeTypes.rdfhandlers.json.
  4. Restart Firefox.

Check for malware

If the problem is still not solved, or if Firefox is opening multiple tabs or windows with unwanted content, consider that your system may be infected by malware. For more information, see Troubleshoot Firefox issues caused by malware.