Test tagname's case-sensitivity when matching SVG-in-XHTML with Element.matches(). On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". Basic cases, tagname alone. PASS document.getElementById('container1').matches('Container') is false PASS document.getElementById('container1').matches('container') is false PASS document.getElementById('container1').matches('CONTAINER') is true PASS document.getElementById('container2').matches('Container') is false PASS document.getElementById('container2').matches('container') is true PASS document.getElementById('container2').matches('CONTAINER') is false PASS document.getElementById('container3').matches('Container') is true PASS document.getElementById('container3').matches('container') is false PASS document.getElementById('container3').matches('CONTAINER') is false PASS document.getElementById('container4').matches('Container') is false PASS document.getElementById('container4').matches('container') is false PASS document.getElementById('container4').matches('CONTAINER') is true PASS document.getElementById('container5').matches('Container') is false PASS document.getElementById('container5').matches('container') is true PASS document.getElementById('container5').matches('CONTAINER') is false PASS document.getElementById('container6').matches('Container') is true PASS document.getElementById('container6').matches('container') is false PASS document.getElementById('container6').matches('CONTAINER') is false PASS document.getElementById('container7').matches('Container') is false PASS document.getElementById('container7').matches('container') is false PASS document.getElementById('container7').matches('CONTAINER') is true PASS document.getElementById('container8').matches('Container') is false PASS document.getElementById('container8').matches('container') is true PASS document.getElementById('container8').matches('CONTAINER') is false PASS document.getElementById('container9').matches('Container') is true PASS document.getElementById('container9').matches('container') is false PASS document.getElementById('container9').matches('CONTAINER') is false Complex selectors PASS document.getElementById('container1').matches('div Container') is false PASS document.getElementById('container1').matches('div container') is false PASS document.getElementById('container1').matches('div CONTAINER') is true PASS document.getElementById('container2').matches('div Container') is false PASS document.getElementById('container2').matches('div container') is true PASS document.getElementById('container2').matches('div CONTAINER') is false PASS document.getElementById('container3').matches('div Container') is true PASS document.getElementById('container3').matches('div container') is false PASS document.getElementById('container3').matches('div CONTAINER') is false PASS document.getElementById('container4').matches('div Container') is false PASS document.getElementById('container4').matches('div container') is false PASS document.getElementById('container4').matches('div CONTAINER') is true PASS document.getElementById('container5').matches('div Container') is false PASS document.getElementById('container5').matches('div container') is true PASS document.getElementById('container5').matches('div CONTAINER') is false PASS document.getElementById('container6').matches('div Container') is true PASS document.getElementById('container6').matches('div container') is false PASS document.getElementById('container6').matches('div CONTAINER') is false PASS document.getElementById('container7').matches('div Container') is false PASS document.getElementById('container7').matches('div container') is false PASS document.getElementById('container7').matches('div CONTAINER') is true PASS document.getElementById('container8').matches('div Container') is false PASS document.getElementById('container8').matches('div container') is true PASS document.getElementById('container8').matches('div CONTAINER') is false PASS document.getElementById('container9').matches('div Container') is true PASS document.getElementById('container9').matches('div container') is false PASS document.getElementById('container9').matches('div CONTAINER') is false PASS successfullyParsed is true TEST COMPLETE