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How can I stop Firefox loading all web pages for all tabs (I have over a thousand tabs!)?

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  • Last reply by Shadow110

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I'm using Firefox 52.8.0 esr and I need to keep it until some of my add-ons get updated for the latest Firefox.

I have over a thousand tabs and that's fine normally because I have Firefox set to load those tabs when I open it but it only actively opens one of those tab's web pages - the one I was on when I closed Firefox last time. So to see any other tab contents I then have to press that tab and it loads the web page for it. For all the other tabs I can see what the web page is from the tab but they aren't loaded.

Now, for reasons that are too long to go into, I am reinstalling Firefox and the only way I can transfer all those tabs is to bookmark them all and import these bookmarks to the new install. I can then open all bookmarks in tabs. The problem is that it literally tries to open and load the web pages of all thousand-plus tabs. Not surprisingly Firefox ultimately crashes due to lack of memory.

So, is there any way to open all those thousand bookmarks as tabs and, in the way that Firefox normally does it on opening, load all tabs but only actively open one tab's web page?

Thanks for any help.

I'm using Firefox 52.8.0 esr and I need to keep it until some of my add-ons get updated for the latest Firefox. I have over a thousand tabs and that's fine normally because I have Firefox set to load those tabs when I open it but it only actively opens one of those tab's web pages - the one I was on when I closed Firefox last time. So to see any other tab contents I then have to press that tab and it loads the web page for it. For all the other tabs I can see what the web page is from the tab but they aren't loaded. Now, for reasons that are too long to go into, I am reinstalling Firefox and the only way I can transfer all those tabs is to bookmark them all and import these bookmarks to the new install. I can then open all bookmarks in tabs. The problem is that it literally tries to open and load the web pages of all thousand-plus tabs. Not surprisingly Firefox ultimately crashes due to lack of memory. So, is there any way to open all those thousand bookmarks as tabs and, in the way that Firefox normally does it on opening, load all tabs but only actively open one tab's web page? Thanks for any help.

Chosen solution

Are you staying with Firefox 52 ESR? In that case, you could consider using the Session Manager extension as an alternate way to store/transfer/restore your sessions.

Note that sessions you save using the extension are saved in a sessions folder in your active Firefox profile folder instead of in the sessionstore-backups folder that Firefox uses for its own session history files. You may want to back up and transfer both folders to your post-reinstall system.

Session Manager is not compatible with Firefox 57+. There are new extensions that may be able to import its data files.

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You can transfer the sessionstore.jsonlz4 file to the profile of the new installation to transfer the tabs.

There should be no need to use bookmarks.


You can copy files like these with Firefox closed to the current profile folder to recover specific data. Note that you should be cautious with copying SQLite database files if you previously had problems.

  • bookmarks and history: places.sqlite
  • bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
  • cookies.sqlite for the Cookies
  • formhistory.sqlite for saved autocomplete Form Data
  • logins.json (passwords) and key4.db (58+) or key3.db (57 and older) (decryption key) for Passwords saved in the Password Manager
    if you only have key3.db then make sure to remove an existing key4.db
  • cert9.db (58+) or cert8.db (57 and older) for (intermediate) certificates stored in the Certificate Manager
    if you only have cert8.db then make sure to remove an existing cert9.db
  • persdict.dat for words you added to the spelling checker dictionary
  • permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
  • sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)
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Chosen Solution

Are you staying with Firefox 52 ESR? In that case, you could consider using the Session Manager extension as an alternate way to store/transfer/restore your sessions.

Note that sessions you save using the extension are saved in a sessions folder in your active Firefox profile folder instead of in the sessionstore-backups folder that Firefox uses for its own session history files. You may want to back up and transfer both folders to your post-reinstall system.

Session Manager is not compatible with Firefox 57+. There are new extensions that may be able to import its data files.

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Thanks for the replies. I did end up using session manager and got the tabs back that way.

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