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Firefox crashes when trying to open with javascript message

  • 4 replies
  • 1 has this problem
  • 3 views
  • Last reply by karen4715

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This message appears when trying to open firefox.

 Java Script Application <BrowserNation_FirstRunPage.init>:TypeError:prefService.prefHasUserValue is not a function

Click on "OK" to clear message as NO Error Codes are displayed, firefox start page goes away, desktop is now showing

Click on firefox icon in task bar to stop firefox.

Problem started on 12/2 after adding holiday themes to the tab bar from author Madona. These have animation in them which doesn't seem to work.

I have tried uninstall and clean installs 2 times. Still have problem. tl

Currently using Chrome browser.

Thanks, Karen

This message appears when trying to open firefox. Java Script Application <BrowserNation_FirstRunPage.init>:TypeError:prefService.prefHasUserValue is not a function Click on "OK" to clear message as NO Error Codes are displayed, firefox start page goes away, desktop is now showing Click on firefox icon in task bar to stop firefox. Problem started on 12/2 after adding holiday themes to the tab bar from author Madona. These have animation in them which doesn't seem to work. I have tried uninstall and clean installs 2 times. Still have problem. tl Currently using Chrome browser. Thanks, Karen

Chosen solution

You can create a new profile to test if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.


You can copy files like these to the current Firefox profile folder to recover specific data.

  • bookmarks and history: places.sqlite
  • bookmark backups: JSON backups in the bookmarkbackups folder
  • SQLite files like cookies.sqlite (cookies) and formhistory.sqlite (saved form data)
  • logins.json and key3.db (decryption key) for Passwords saved in the Password Manager
  • cert8.db and possibly cert_override.txt for (intermediate) certificates stored in the Certificate Manager
  • persdict.dat for words you added to the spelling checker dictionary
  • permissions.sqlite for Permissions and possibly content-prefs.sqlite for other Site Preferences
  • sessionstore.js for open tabs and pinned tabs and tab groups

You can use this button to go to the current Firefox profile folder:

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All Replies (4)

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This can be caused by a broken extension that isn't working properly.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window
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My start/home only stays on the desktop for 30 SECONDS before it disappears. I can't do any type of fixing that requires having the browser OPEN. I'm getting to mozilla support by using the CHROME browser. What is required to do a 1st time install of firefox? what left behind files need deleteing? thanks for your help

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Chosen Solution

You can create a new profile to test if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.


You can copy files like these to the current Firefox profile folder to recover specific data.

  • bookmarks and history: places.sqlite
  • bookmark backups: JSON backups in the bookmarkbackups folder
  • SQLite files like cookies.sqlite (cookies) and formhistory.sqlite (saved form data)
  • logins.json and key3.db (decryption key) for Passwords saved in the Password Manager
  • cert8.db and possibly cert_override.txt for (intermediate) certificates stored in the Certificate Manager
  • persdict.dat for words you added to the spelling checker dictionary
  • permissions.sqlite for Permissions and possibly content-prefs.sqlite for other Site Preferences
  • sessionstore.js for open tabs and pinned tabs and tab groups

You can use this button to go to the current Firefox profile folder:

more options

Thanks for providing all the information about "Profiles". Found a file in there called "Christmas". Deleted it and all is right again. Thanks again for your time and help. Karen4715