start up tabs

If Firefox is no longer opening your saved startup tabs, first check your browser settings. Go to Settings → Home and verify that "Open previous windows and tabs" is enabled. Also review the homepage and startup preferences to ensure your selected pages are still configured correctly.

This issue can sometimes happen after a browser update, profile changes, or if Firefox settings were reset unexpectedly. It can be particularly noticeable for users who regularly keep multiple pages open, such as navigation tools, map resources, location searches, or other reference tabs used for daily browsing and planning.

You can also check History → Recently Closed Windows to restore lost tabs. If the issue continues, try disabling browser extensions one at a time or launch Firefox in Troubleshoot Mode to see whether an add-on is affecting startup behavior.

In 152 the Settings has been redesigned a little bit. Right now it's hidden under Custom URLs… in the Home and startup section.