See https://github.com/webcompat/web-bugs/issues/412 > `getComputedStyle()` doesn't throw in Chrome even if you pass a text node to it. That's why the failure occurs only in Firefox. Bugs to make sure other browsers follow the spec too: - [Webkit-138584](https://bugs.webkit.org/show_bug.cgi?id=138584) - [Blink-431915](https://code.google.com/p/chromium/issues/detail?id=431915) See [Test Case](http://hallvord.com/temp/moz/bug/wc412.htm)