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how do i remove the user.js file so mozilla opens in search mode

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  • 2 有這個問題
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  • 最近回覆由 cor-el

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something happened and now every time I open mozilla it opens the last web site I was on. I read that there is a user.js file that was created. I did not create anything and want it all removed or I won't be able to use mozilla. I don't know how to remove the user.js file please help in non technical terms

something happened and now every time I open mozilla it opens the last web site I was on. I read that there is a user.js file that was created. I did not create anything and want it all removed or I won't be able to use mozilla. I don't know how to remove the user.js file please help in non technical terms

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If you had included your troubleshooting information then could have seen if the user.js file is present because that information is included.

You can check that on the about:support page.


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

  • Help > Troubleshooting Information > Profile Directory: Show Folder (Linux: Open Directory; Mac: Show in Finder)

Windows hides some file extensions by default. Among them are .html and .ini and .js and .txt, so you may only see the User file name without file extension. You can see the real file type (file extension) in the properties of the file via the right-click context menu in Windows Explorer.


The user.js file is only present if you or other software has created this file and normally it wouldn't be there. You can check its content with a plain text editor (right-click: Open with) if you didn't create this file yourself.

The user.js file is read each time Firefox is started and initializes preferences to the value specified in this file, so preferences set via user.js can only be changed temporarily for the current session.