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How do I stop Firefox 4 from automatically entering Private Browsing mode?

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It appears to randomly enter Private Browsing mode. When I check the history when Firefox is open, it will appear but when I exit and restart The history is clear. I think it is possibly triggered by https sites but I'm not sure, so it appears to be random. I have never used nor turned on Private Browsing.

It appears to randomly enter Private Browsing mode. When I check the history when Firefox is open, it will appear but when I exit and restart The history is clear. I think it is possibly triggered by https sites but I'm not sure, so it appears to be random. I have never used nor turned on Private Browsing.

Modified by cleverlymadeup

Chosen solution

You have a corrupted user agent the identifies you as Firefox/3.0.10

  • Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.10; .NET CLR 3.0; ffco7) Gecko/2009042316 Firefox/3.0.10

See also:


  • You enter Private Browsing mode if you select: Tools > Options > Privacy > History: Firefox will: "Never Remember History"
  • To see all History and Cookie settings, choose: Tools > Options > Privacy, choose the setting Firefox will: Use custom settings for history
  • Uncheck: [ ] "Automatically start Firefox in a private browsing session"

See also:

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).

  • Don't make any changes on the Safe mode start window.

See:

Read this answer in context 👍 3

All Replies (5)

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Firefox 3.0.10 doesn't have a Private Browsing mode, that was added to Firefox in version 3.5.

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It's not version 3.0.10. Like the question states it's Firefox 4

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Chosen Solution

You have a corrupted user agent the identifies you as Firefox/3.0.10

  • Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.10; .NET CLR 3.0; ffco7) Gecko/2009042316 Firefox/3.0.10

See also:


  • You enter Private Browsing mode if you select: Tools > Options > Privacy > History: Firefox will: "Never Remember History"
  • To see all History and Cookie settings, choose: Tools > Options > Privacy, choose the setting Firefox will: Use custom settings for history
  • Uncheck: [ ] "Automatically start Firefox in a private browsing session"

See also:

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the add-ons is causing the problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).

  • Don't make any changes on the Safe mode start window.

See:

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Actually it seems to be something with the FireGestures. I had uninstalled FF and deleted the preferences and such. So I had a fresh copy of the browser. It still did the same thing. Disabled FireGestures and it stopped doing it.

Now I need to find a good mouse gesture addon

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Actually this wasn't solved. It's not really Private Browsing as much as history just stops being added. It's not an add-on, it's something with FireFox 4. It seems that https triggers it.