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My previous session gets automatically restored when I open Firefox and I want to make it stop, but do not know how.

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Firefox 39.0 just installed on my computer and now every time I close out of firefox and then open it again my previous session comes back up automatically. This has not happened previously and I do not think that I changed any setting to get it to do this. How do I get Firefox to stop opening up my previous session?

Firefox 39.0 just installed on my computer and now every time I close out of firefox and then open it again my previous session comes back up automatically. This has not happened previously and I do not think that I changed any setting to get it to do this. How do I get Firefox to stop opening up my previous session?

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Hi, please see - How to set the home page, and under the heading 'Restore the default home page,' make sure that 'When Firefox starts' isn't set to 'Show my windows and tabs from last time'.

If your question is resolved by this or another answer, please take a minute to let us know. Thank you.

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You may have a corrupt sessionstore file.

Type about:support in the address bar and press enter.

Under the page logo on the left side you will see Application Basics. Under this find Profile Folder. To it’s right press the button Show Folder. This will open your file browser to the current Firefox profile. Now Close Firefox.

Locate the sessionstore files (There may be more then one). Then rename or delete them. Restart Firefox.

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You can check if you have a user.js file in the Firefox profile folder that sets the browser.sessionstore.resume_session_once pref to true.

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

Windows hides some file extensions by default. Among them .html and .ini and .js and .txt, so you may only see a 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 will only be present if you or other software has created this file and normally won't be present.

You can check its content with a plain text editor (right-click: "Open with"; do not double-click). 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.

Delete the user.js file if you didn't create this file yourself.

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were is the session restore on/off switch in the options section? It happens when Firefox hangs and has to be terminated, and only adds to the bother.

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Hi Magnatum, it is normal for Firefox to try to restore your previous session automatically after a crash. If you prefer to have the choice, you can change a setting so that Firefox asks you which windows and tabs to restore after a crash, or whether to simply start a new session. Here's where you do that:

(1) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(2) In the search box above the list, type or paste sess and pause while the list is filtered

(3) Double-click the browser.sessionstore.max_resumed_crashes and edit the value from 1 to 0 (that's a zero) and OK the change.

After you kill Firefox the next time, when you start up, it should show a screen that says "This is embarrassing" and the option to simply start a new session is at the bottom of that page.

If that doesn't happen, investigate whether you might have a user.js file. This article has a section on that: How to fix preferences that won't save.

And finally, Firefox shouldn't hang! You may want to start a new question about that if it happens more than a couple times a month. You can use this link, and scroll down past the suggestions to continue submitting your question if they are not relevant/helpful: https://support.mozilla.org/questions/new/desktop/fix-problems