modernizr/feature-detects/css/generatedcontent.js

Modernizr is a JavaScript library that detects HTML5 and CSS3 features in the user’s browser.

/*!
{
  "name": "CSS Generated Content",
  "property": "generatedcontent",
  "tags": ["css"],
  "warnings": ["Android won't return correct height for anything below 7px #738"],
  "notes": [{
    "name": "W3C CSS Selectors Level 3 spec",
    "href": "https://www.w3.org/TR/css3-selectors/#gen-content"
  },{
    "name": "MDN article on :before",
    "href": "https://developer.mozilla.org/en-US/docs/Web/CSS/::before"
  },{
    "name": "MDN article on :after",
    "href": "https://developer.mozilla.org/en-US/docs/Web/CSS/::before"
  }]
}
!*/
define(['Modernizr', 'testStyles'], function(Modernizr, testStyles) {
  testStyles('#modernizr{font:0/0 a}#modernizr:after{content:":)";visibility:hidden;font:7px/1 a}', function(node) {
    // See bug report on why this value is 6 crbug.com/608142
    Modernizr.addTest('generatedcontent', node.offsetHeight >= 6);
  });
});