This test checks that background-repeat-x/y are not parsed or supported On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PASS window.getComputedStyle(document.getElementById('test1')).getPropertyValue('background-repeat') is "repeat" PASS window.getComputedStyle(document.getElementById('test2')).getPropertyValue('background-repeat') is "repeat" PASS window.getComputedStyle(document.getElementById('test3')).getPropertyValue('background-repeat') is "repeat-y" PASS window.getComputedStyle(document.getElementById('test4')).getPropertyValue('background-repeat') is "repeat-x" PASS CSS.supports('background-repeat-x: inherit') is false PASS CSS.supports('background-repeat-x', 'inherit') is false PASS CSS.supports('background-repeat-y: inherit') is false PASS CSS.supports('background-repeat-y', 'inherit') is false PASS successfullyParsed is true TEST COMPLETE