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unclean shutdown tab restore

radmilasha
radmilasha
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I try to configure firefox with the strictest privacy settings at all times, but there are some cases where privacy leaks are quite annoying. This problem is particularly annoying.

Firefox has a feature to restore tabs from a previous session on startup. Obviously I do not use this feature, not wittingly anyway. When firefox is shutdown cleanly, there is not a problem. When I kill firefox via SIGTERM or signal 9 then firefox will shutdown, but then when I start it up again, it will restore the previous session's tabs without even asking (not even the usual "do you want to restore?" page). This should not be. Firefox should startup as a clean slate.

While I understand in the case of a kill -9 that firefox is not able to delete temporary files, firefox is able to do this on a SIGTERM, but apparently it does not. But on startup, firefox should be configurable to delete any residual temporary files it discovers, instead of reloading (read: re-sending HTTP requests) my previous tabs, especially with no prompt.

How can I resolve this problem?

I try to configure firefox with the strictest privacy settings at all times, but there are some cases where privacy leaks are quite annoying. This problem is particularly annoying. Firefox has a feature to restore tabs from a previous session on startup. Obviously I do not use this feature, not wittingly anyway. When firefox is shutdown cleanly, there is not a problem. When I kill firefox via SIGTERM or signal 9 then firefox will shutdown, but then when I start it up again, it will restore the previous session's tabs without even asking (not even the usual "do you want to restore?" page). This should not be. Firefox should startup as a clean slate. While I understand in the case of a kill -9 that firefox is not able to delete temporary files, firefox is able to do this on a SIGTERM, but apparently it does not. But on startup, firefox should be configurable to delete any residual temporary files it discovers, instead of reloading (read: re-sending HTTP requests) my previous tabs, especially with no prompt. How can I resolve this problem?

All Replies (1)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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You can prevent Firefox from automatically restoring after a crash. Instead, Firefox will give you the choice of restoring or loading your home page. Here's how to do that:

(A) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(B) In the search box above the list, type or paste sess and pause while the list is filtered

(C) Double-click the browser.sessionstore.max_resumed_crashes preference and change the value from 1 to 0 and OK that.

Note: I suggest not changing any other sessionstore preferences without researching them first.

Speaking of privacy, do you already block Firefox from storing session cookies in the session history file? These are the relevant preferences:

  • browser.sessionstore.privacy_level => set to 2 (default is 0)
  • browser.sessionstore.privacy_level_deferred => set to 2 (default is 1)