Make sure that you not run Firefox in permanent Private Browsing mode.

• https://support.mozilla.com/kb/Private+Browsing
• You enter Private Browsing mode if you select: Firefox > Preferences > Privacy > History: Firefox will: "Never Remember History"
• To see all History and Cookie settings, choose: Firefox > Preferences > Privacy, choose the setting Firefox will: Use custom settings for history
• Deselect: [ ] "Permanent Private Browsing mode"

It's not in private browsing and I checked the custom history settings. Everything's the way it should be.

Check that session restore is still working.

• http://kb.mozillazine.org/Session_Restore

It is possible that there is a problem with the files sessionstore.js and sessionstore.bak in the Firefox Profile Folder.

Delete the files sessionstore.js and sessionstore.bak in the Firefox Profile Folder.

• Help > Troubleshooting Information > Profile Directory: Open Containing Folder
• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/sessionstore.js

If you see files sessionstore-##.js with a number in the left part of the name like sessionstore-1.js then delete those as well.

Deleting sessionstore.js will cause App Tabs and Tab Groups to get lost, so you will have to create them again (make a note).

Er, does App tabs and Tab Groups have anything to do with bookmarks?

It has to do with restoring tabs via session restore on the next start. If you delete the file that stores session data in case of problems with it then you lose App Tabs. That may not apply to you if you do not use them, but may apply to others who read this.

Well, I tried what you said, deleted those files, and now firefox won't open at all. When I click it it jumps once - all applications do this except they usually jump a couple more times first - and the nothing. It simply won't do anything now.

Which files did you remove and from which location (folder)?

If they are still in the trash then try to restore them.

Create a new profile as a test to check if your current profile is causing the problems.

See:

• Basic Troubleshooting: Make a new profile

If that new profile works then you can transfer some files from the old profile to that new profile (be careful not to copy corrupted files)

See:

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

The files I deleted were the ones you told me to delete. sessionstore.js, sessionstore.bak, sessionstore-1.js. I deleted those files in the profile folder that I had renamed to 'search.sqlite' for another problem I was having, and then there was another folder named 'Profiles' that hadn't been there before so I deleted those files from there too.

There's one file I can't get back. It was a sessionstore.js. The reason why I can't get it back is because it replaced the other sessionstore.js that I had pulled out of the other folder.

That link you gave me for creating a new profile doesn't give instruction for how to do it on a mac.

You can't rename or delete folders like that. That will corrupt the Firefox Profile Folder

If you have a file profiles.ini then delete that file to make Firefox create a new default profile.

• http://kb.mozillazine.org/profiles.ini_file
• http://kb.mozillazine.org/Recovering_a_missing_profile

I renamed the profile folder before because of a link you gave me in another thread for another problem and it worked. I also haven't deleted anything you haven't said to.

I deleted the profiles.ini file. I also went through terminal to try and get to profile manager, like it said to in your link, but it said there was no such file or directory.

Is there a way that I can just reinstall firefox and get all my bookmarks to it? It seems like there's too many things wrong with the firefox on my computer. Maybe if I reinstall I won't have to go through all this extra stuff. Might that work?

I would never ask to rename a folder that way.

It was probably suggested in a support article or by me to rename a file in the Firefox Profile Folder to test for file corruption.

Was this about a corrupted file places.sqlite?

Did you try to create and use a new profile?

See:

• Basic Troubleshooting: Make a new profile

If that new profile works then you can transfer some files from the old profile to that new profile (be careful not to copy corrupted files)
See:

• https://support.mozilla.com/kb/Recovering+important+data+from+an+old+profile
• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

I do not know how to create a new profile. The link you gave me for making a new profile tells me to use the instructions in Managing Profiles to open profile manager, but it only gives instructions on how to do it on windows, not mac which is what I have.

There is a menu in the bar at the right on the page with the KB article that allows to select the Operating System and the Firefox version, so make sure that you get the content for Mac OS X and Firefox 4.

• https://support.mozilla.com/kb/Basic+Troubleshooting#w_8-make-a-new-profile

Oh okay, can't believe I didn't see that.

I made absolutely sure that firefox was completely closed, that it wasn't running in the background or anything, then entered terminal and typed in what it said to but it said there was 'No such file or directory'.

I made sure that I typed in precisely what it said to but still nothing.

Well, a few minutes ago I accidentally clicked on firefox out of habit, not realizing that it wouldn't work. Except, well, this time it did work. For one moment I was all excited until I saw that all my bookmarks were gone and then nearly had a heart attack.

So I looked and saw that firefox had somehow made itself a new profile and then I figured out how to restore my bookmarks from the other profile and everything is pretty much back in order.

It still won't ask to save tabs though. I went back into about:config to check that all those things were set to true but still no luck.

Firefox 4 saves the previous session automatically, so there is no longer need for the dialog asking if you want to save the current session.
Use "File > Exit" or "Firefox > Exit" (Mac: "Firefox > Quit Firefox") if you want to restore multiple windows.
You can use "History > Restore Previous Session" to get the previous session at any time.
You may need to click the orange/gray Firefox button to see History.
There is also a "Restore Previous Session" button on the default about:home Home page.

Another possibility is to use:

• Firefox/Tools > Options > General > Startup: "When Firefox Starts": "Show my windows and tabs from last time"

You can set the warn prefs on the about:config page to true via the right-click context menu or toggle the value with a double left-click.

• browser.showQuitWarning, see http://blog.zpao.com/post/3174360617/about-that-quit-dialog
• browser.tabs.warnOnClose, see http://kb.mozillazine.org/About%3Aconfig_entries
• browser.warnOnQuit , see http://kb.mozillazine.org/browser.warnOnQuit
• browser.warnOnRestart , see http://kb.mozillazine.org/browser.warnOnRestart

Firefox 5 include a new style of tabs save. You can restore the previous session doing: Edit->Preferences->General->When Firefox starts: (then three options)

1. Your fixed home page.
2. A blank page.
3. Windows and tabs that where opened last time you accessed the net.

In order to restore last session you must select option number 3.

I hope it helps good fellows.

Yeah, I know I can restore tabs like that. I'd just rather it be through the dialog like before. So that it doesn't restore tabs every time I log in. And so that when I log in next time it'll automatically come up so I don't forget about it.

Guess I'll have to try to get used to it though, if there's no way to get the dialog back. Thanks for your help guys.

I believe you can replace the previous functionality with a plug-in, I'm on the same boat and looking for it. There are several of them and will need to try and see which one is the best.

This problem has to do with your history settings. If you are already getting the "Save and Quit" dialog box, temporarily turn off "Clear history when Firefox closes" (Tools > Options > Privacy) to see if it now works.

If it does work, turn it back on and click the "Settings" button next to it. Untick the box for "Browsing History". This setting is not needed if you have the main option "Remember my browsing history for at least X days" unticked.

Remember: this solution is only for people who are already getting the "Save and Quit" dialog box, but the tabs are not opening when you start Firefox.