Browser Specific HTML Tags and Attributes

Question

There are tons HTML tags, values, and attribute/value pairs that are vendor specific and as a result are either not well-known or are poorly documented. For instance:

<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">

If the browser is IE the page will either be rendered in chrome frame or the latest IE rendering engine.

Another example:

<meta name="viewport" content="width=device-width; initial-scale=1.0; maximum-scale=1.0;">

This markup tweaks the mobile browser's display size to better fit the content to a smart-phone screen.

Both of these examples are highly usable, but moreover highly undocumented. You only discover them if you are lucky enough to stumble across a particular blog post on it, or if you are the kind of dude who likes to read through browser specifications (not likely).

This brings me to my question: what web resources are available where I can discover, learn, and/or reference browser-specific markup like this?

Answer 1

Unfortunately vendor-specific behavior is rampant with browsers. It's getting better over time, but there is no "one true source" that contains everything you need to know. To understand exact behavior you'll need to reference each targeted browser individually. If there is no documentation on the behavior you'll actually need to compose a series of tests yourself.

I don't usually do this though. In general, I learn things like this through a combination of experimentation, google searching, and time. New browser hacks are discovered semi-frequently through trial and error mostly.

With that said, searching for "CSS tests" is a good way to come across all sorts of interesting stuff:

http://www.brunildo.org/test/

Answer 2

Just today I came across a page in Wikipedia that partially answered this question. It provides a list of proprietary HTML elements and properties and their support across various rendering engines. Just thought I'd post this in case someone else was looking for an answer here.

http://en.wikipedia.org/wiki/Comparison_of_layout_engines_(Non-standard_HTML)

Unfortunately, I have not yet found any documentation on HTML attribute values for various browsers.

The more I look the more I realize now that the best--and probably only--place to find proprietary HTML elements/attributes/values is by searching through the platform's documentation.