Clear Cookies & Cache

• https://support.mozilla.com/en-US/kb/Template:clearCookiesCache

Clear the Network Cache

• https://support.mozilla.com/en-US/kb/How%20to%20clear%20the%20cache#w_clear-the-cache

Using the Adobe Reader plugin with Firefox

• https://support.mozilla.com/en-US/kb/Using%20the%20Adobe%20Reader%20plugin%20with%20Firefox

Opening PDF files within Firefox

• https://support.mozilla.com/en-US/kb/Opening%20PDF%20files%20within%20Firefox

Check and tell if its working.

this isn't really restricted to the pdf plugin (adobe's or foxit's). i've sene this happening for java applets and logmein's plugin for remote access. so this isn't really limited to a certain 3rd party plugin. upto fx5 this worked just fine and i can in fact just go back to fx5 and see the behaviour disappear. the issue remains in all versions from 6 to 9.

hw acceleration is disabled, but enabling doesn't change anything either. i've seen this happening on 2 systems with different hw specs (different cpu and gfx manufacturer). i disabled all addons as well to exclude the possibility of either of them doing odd stuff.

i attached an image to the post to show you what this looks like. the red stuff you can see is actually from the desktop. so the window gets semi transparent. in fact the brightness stems from the transparency. if i put somethign dark behind firefox it becomes actually readable.

and for that matter resetting cache obviously did nothing.

-> Close Firefox (click Firefox button and click Exit)

-> Start Firefox in Safe Mode by holding down SHIFT key while starting Firefox

• As an alternative method, by using Win + R key combination and enter one of the following in the Windows Run box:
  • firefox -safe-mode
  • "C:\Program Files\Mozilla Firefox\firefox.exe" -safe-mode
  • "C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -safe-mode

-> Firefox Safe Mode window will appear -> DON'T SELECT ANY OPTIONS, just click Continue in Safe Mode

Troubleshooting extensions and themes

• https://support.mozilla.com/en-US/kb/Troubleshooting%20extensions%20and%20themes

Update All your Firefox Plugins

• https://www-trunk.stage.mozilla.com/en-US/plugincheck/
• http://www.mozilla.com/en-US/plugincheck/

Check and tell if its working.

Also see these posts:

• https://support.mozilla.com/en-US/questions/866570#answer-236560
• https://support.mozilla.com/en-US/questions/865066#answer-236338

Check and tell if its working.

oh indeed http://blog.mozilla.com/addons/2011/08/22/firefox-6-breaking-themes-plugin/

was the reason for it. didn't quite expect the theme to be the reason for it. guess i should kick the theme author to fix his style if he isn't already aware of it.

thanks for your help. this was driving me mad insane.