Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

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

  • 1 cavab
  • 2 have this problem
  • 1 view
  • Last reply by cor-el

more options

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)

more options

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.