Avatar for Username

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

This thread was archived. Please ask a new question if you need help.

Purpose of the "@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */" css code?

  • 5 replies
  • 1 has this problem
  • 50 views
  • Last reply by Rick W

Rick W
Rick W
more options

Can anyone please explain the purpose of the 

   @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */

css code, which is often recommended to head any userchrome.css text inside the chrome folder? What happens when you omit this @namespace url line?

Can anyone please explain the purpose of the @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */ css code, which is often recommended to head any userchrome.css text inside the chrome folder? What happens when you omit this @namespace url line?

Chosen solution

Hi, have a read of https://www.userchrome.org/adding-style-recipes-userchrome-css.html

If your question is resolved by this or another answer, please take a minute to let us know. Thank you!

Read this answer in context 👍 1

All Replies (5)

Rick W
Rick W Question owner
more options

Is it simply an advertisement for Firefox XML User Interface Language?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

You use this line to set the namespace for the code on that page.

Rick W
Rick W Question owner
more options

Why does one need to set a namespace?? What happens if it is not done?

Scribe
Scribe
more options

Chosen Solution

Hi, have a read of https://www.userchrome.org/adding-style-recipes-userchrome-css.html

If your question is resolved by this or another answer, please take a minute to let us know. Thank you!

Rick W
Rick W Question owner
more options

Thanks, Scribe, that is very useful:

Scribe said

Hi, have a read of https://www.userchrome.org/adding-style-recipes-userchrome-css.html

Good to know it is safe to leave that namespace line out of my userchrome.css code.