In about:config the following setting is 'true' by default: browser.sessionstore.resume_from_crash. The default value for the following is 1: browser.sessionstore.max_resumed_crashes You can check those by opening a new tab and entering about:config in the url-bar. On the General page of Options, have you selected the setting "Restore previous session"?

If you have a problem with losing the history after a crash then it is possible that there are problems with the places.sqlite database (bookmarks and history). Bookmarks can be restored automatically from a backup if a new places.sqlite is created, but the history is lost.

Use one of these to close Firefox if you are currently doing that by clicking the close X on the Firefox Title bar.

• "3-bar" menu button -> Exit (Power button)
• Windows: File -> Exit
• Mac: Firefox -> Quit Firefox
• Linux: File -> Quit

If you have submitted crash reports, please post the IDs of one or more recent crash reports that start with "bp-".

• bp-xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

You can find the report ID of recent crash reports on the "Help -> Troubleshooting Information" (about:support) page.

• click the "All Crash Reports" button on this page to open the about:crashes page and see all crash reports.

Alternatively you can open about:crashes via the location/address bar.

See also:

• https://support.mozilla.org/en-US/kb/mozillacrashreporter