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Why do all <h3> tags have red background on all websites?

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  • Last reply by cor-el

smallvoice
smallvoice
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Sometime today all of the h3 tags on any page, any website began appearing with a red background color applied. When I check the element with Firebug, it shows the color being applied from file html.css <System>.

Checking same pages in Internet Explorer, Opera, Chrome and Safari -- all in Windows -- this doesn't happen.

Sometime today all of the h3 tags on any page, any website began appearing with a red background color applied. When I check the element with Firebug, it shows the color being applied from file html.css <System>. Checking same pages in Internet Explorer, Opera, Chrome and Safari -- all in Windows -- this doesn't happen.

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).

See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

You can also try "Reset all user preferences to Firefox defaults" on the Safe mode start window.