As of version 19, Chrome\'s Web Inspector has an experimental feature called "snippets support". Here is how to activate it:
Open chrome:flags, ena
I'm unable to activate that experiment myself (there's no Developer Tools experiments in my chrome:flags, but from Safari, I found this explanation:
In short, it "is a little utility that allows you to enter blocks of HTML and CSS and have it rendered on the fly".
From the blog post, it seems it is buggy in Safari, so maybe Chrome has not implemented it yet.