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Firefox 13 thinks and looks as it is running in Windows XP, no Aero Windows Title, shows user agent NT5.1

  • 9 replies
  • 3 have this problem
  • 3 views
  • Last reply by goofy_kl9

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Firefox 13 has Windows Classic window title and buttons, even though it's running on Windows Vista Aero. It reports wrong user agent (NT5,1), thinks it's running on XP, which is consistent with the looks, and I don't know how to solve it.

Previous versions worked fine. This started after FF13 update.

Any thoughts?

Firefox 13 has Windows Classic window title and buttons, even though it's running on Windows Vista Aero. It reports wrong user agent (NT5,1), thinks it's running on XP, which is consistent with the looks, and I don't know how to solve it. Previous versions worked fine. This started after FF13 update. Any thoughts?

Modified by kriket

All Replies (9)

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Modified by philipp

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Make sure that you do not run Firefox in compatibility mode.
You can open the Properties via the right-click context menu of the Firefox desktop shortcut and check that in the "Compatibility" tab.
Make sure that all items are deselected in the "Compatibility" tab of the Properties window.

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No it isn't. Already checked that. I also did a Reset Settings in Firefox 13 - still no luck, reports user agent NT5.1 and no Windows Aero window title and buttons

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Did you try to change the Windows XP (SP2) setting to no compatibility?

Did you also check the settings for the Firefox.exe program in the Firefox program folder (C:\Program Files\Mozilla Firefox\)?

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firefox.exe - same deal, no compatibility mode set. And even if it was, why would it be? I wouldn't have set it myself. Never had this problem with earlier versions. What's changed?

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It still shows a Windows XP (SP2) setting as the default, so that setting may have been selected elsewhere as the default.

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Yes, it's always been the default setting, but the checkbox isn't checked, so it doesn't run it in any compatibility mode regardless of what the default compatibility mode is, right? I mean, if it makes any difference what the unactive default compatibility mode is, than it's a bug too, isn't it?

Let's try changing the default compatibility mode, see if that makes any difference.

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What Compatibility mode should I un-set, in order to make this go away? It doesn't make any sense to me, I must admit.

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Hi all my Firefox started freezing after an update don't know which and even after cleaning folder etc. V13 now freezes Vista system. Setting to XP compat mode makes it run and running as Admin on Vista Makes it run. I wont run as admin for safety reasons but I have set as Xp compat mode as that works. Something is wrong out there. I hope they fix it because FF is my other favorite browser.

Modified by goofy_kl9