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Firefox doesn't display CSS style

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On some sites (Stack Exchange network, http://www.cyberforum.ru) Firefox shows "Basic page style" the same as "No style". Firefox is latest version, Win7 64 bit. "Log in" button on Stack Exchange also doesn't work.

On some sites (Stack Exchange network, http://www.cyberforum.ru) Firefox shows "Basic page style" the same as "No style". Firefox is latest version, Win7 64 bit. "Log in" button on Stack Exchange also doesn't work.

All Replies (2)

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Separate Security Issue, please update your Flash 18.0 r0 by removing it with this tool : https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html If you use it Reinstall with Flash Player Version: 30.0.0.154 Current Version https://get.adobe.com/flashplayer/otherversions/ Step 1: Select Operating System Step 2: Select A Version (Firefox, . . . .) Note: Other software is offered in the download. <Windows Only>

Please try : SAFE MODE

In Firefox Safe mode these changes are effective:

  • all extensions are disabled (about:addons)
  • default theme is used (no persona)
  • userChrome.css and userContent.css are ignored (chrome folder)
  • default toolbar layout is used (file: localstore-safe.rdf)
  • Javascript JIT compilers are disabled (prefs: javascript.options.*jit)
  • hardware acceleration is disabled (Options > Performance > Uncheck to view)
  • plugins are not affected
  • preferences are not affected

TEST''''is issue still there ?

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Thank you for sharing your extensions list. I notice you have Adblock Plus and a proxy connection add-on. The Safe Mode test will assist in discovering whether either of those could be causing the problem.

More generally, does your Firefox ever report any secure connection problems with HTTPS addresses? If so, we should sort that out first.

Firefox has a couple different security error pages, and there are corresponding help articles for each one: