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How to delete history, cookies, and cache on OPEN

thelibrarytech
thelibrarytech
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I administer public access computers in a public library. We use Firefox as our primary browser, and I have configured it to clear cache, history, and cookies on exit to protect patron privacy.

Recently, I have experienced a few instances where this did not work. Upon confirming that there weren't any minimized windows open in the taskbar, I could re-open the browser and access the previous patron's email inbox. This should not happen because clearing the cookies should remove any active logins.

My hypothesis for why this happened is that the Firefox process did not terminate properly, preventing it from clearing the data.

My question is: Is there a way to tell Firefox to clear the data when it *OPENS* as well as closes? This would allow for the data to be wiped if Firefox crashes or does not shutdown properly.

I administer public access computers in a public library. We use Firefox as our primary browser, and I have configured it to clear cache, history, and cookies on exit to protect patron privacy. Recently, I have experienced a few instances where this did not work. Upon confirming that there weren't any minimized windows open in the taskbar, I could re-open the browser and access the previous patron's email inbox. This should not happen because clearing the cookies should remove any active logins. My hypothesis for why this happened is that the Firefox process did not terminate properly, preventing it from clearing the data. My question is: Is there a way to tell Firefox to clear the data when it *OPENS* as well as closes? This would allow for the data to be wiped if Firefox crashes or does not shutdown properly.

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Firefox should log the closing progress in sessionCheckpoints.json in the profile folder and if there are unfinished tasks detected on startup then these should be done. Firefox can store session data in sessionstore.jsonlz4 including cookies. To prevent storing cookies as part of session restore, you can set the browser.sessionstore.privacy_level pref to 2 on the about:config page.

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.

thelibrarytech
thelibrarytech Question owner
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cor-el said

To prevent storing cookies as part of session restore, you can set the browser.sessionstore.privacy_level pref to 2 on the about:config page.

Thanks, I'll try that.