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I am using the add-on stylish in Firefox 8.0. I particularly like a plain style and I want to apply to all website. Can I do that? I tried *.com and it doesn't work.

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up vote 4 down vote accepted

You can apply a style to all websites by using the XHTML namespace:

@namespace url(;

Your CSS here.

Alternatively, to only modify the Firefox UI, you would use the XUL namespace:

@namespace url(;

So, if you do not include a namespace, Stylish will modify all elements in Firefox.



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Can you give an working example? Thanks. – lamwaiman1988 Dec 1 '11 at 3:41
I tried the first one you wrote and it didn't work. – lamwaiman1988 Dec 1 '11 at 4:06
@gunbuster363 See my edit. :) – iglvzx Dec 1 '11 at 4:21
It's working now. – lamwaiman1988 Dec 1 '11 at 5:42

I found the XHTML namespace rule @namespace url(; to apply to everything, web sites and the Firefox UI (chrome) alike.

To style all web sites, I use the following @document rule instead (tested with FF28.0 and Stylish 1.4.3):

@-moz-document url-prefix(http://), url-prefix(https://) {
    /* Make all Links UPPERCASE */
    a {
        text-transform: uppercase !important;

Documentation on Mozilla Developer Network:

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