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Prevent Firefox from opening multiple sessions at the same time

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  • 1 has this problem
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  • Last reply by Shadow110

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Firefox regularly locks up. When opening Task Manager, I find five or more firefox sessions running at the same time. Have to stop each process before I can restart firefox. Getting real tired of this.

Firefox regularly locks up. When opening Task Manager, I find five or more firefox sessions running at the same time. Have to stop each process before I can restart firefox. Getting real tired of this.

All Replies (2)

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Is there anything in the Windows Event log about these hangs?

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window

Modified by cor-el

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Hi, since mention locks up and your on Win 7 I would gather this is a older system.

Firefox is suppose to have multiple instances running and you can lower the amount by doing this : https://support.mozilla.org/en-US/kb/performance-settings Restart Firefox after making changes. Test.

Running less used Extensions/addons would be good also to save on ram/memory being used.

If still issues suggest you backup your bookmarks : https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer Backup your Profile : https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles Then uninstall Firefox and install Firefox ESR after backing up only : https://support.mozilla.org/en-US/kb/switch-to-firefox-extended-support-release-esr

Note : you can try the Refresh but backup 1st.