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Start your free trialFábio Tavares da Costa
11,985 PointsHow to Access the User Agent Style Sheet?
Hi,
I hear developers talk about styles applied by User Agents. How can we access these rules?
Cheers!
3 Answers
Christopher Vesti
1,622 PointsUser Agent Style sheets simply refer to the default styles that browsers apply to web pages. It is of the lowest importance considering User Styles and Author styles will overwrite these. Each browser is a little different in how it displays "unstyled" html.
If you want to see first hand how browsers display html, create a simple .html document with different header, paragraph and image elements and open it with different browsers.
billmei
3,540 PointsHi Fábio Tavares da Costa, you can find the full list of all styles in each User Agent Stylesheet in the following locations:
- Mozilla Firefox: https://dxr.mozilla.org/mozilla-central/source/layout/style/res/html.css
- Google Chrome: https://chromium.googlesource.com/chromium/blink/+/master/Source/core/css/html.css
- Safari (WebKit): https://trac.webkit.org/browser/trunk/Source/WebCore/css/html.css
- Internet Explorer: You can't view Internet Explorer's UA Stylesheet because it's not open source.
Fábio Tavares da Costa
11,985 PointsI will do this,
Still, the style sheet itself should be accessible client side. Maybe a plain html file will make the browse reveal it's CSS URI.
Fábio Tavares da Costa
11,985 PointsFábio Tavares da Costa
11,985 PointsOk,
Firefox has an option we can toggle on/off to show browser styles.
In Chrome I see user agent stylesheet in the upper right corner. That's the stylesheet I am looking for.
Plain html will show fragments of computed styles like:
Where is the complete list of rules?