v2.0.0: Apparently, the GoogleWebComponents team is really mingy with the README.md and decides to put everything as comment in the code so it can be displayed with iron-component-page. It would be nice if there’s some text in the README at least. Took me really a lot of time to simplify the demo, even though it’s still complicated to somewhat extent. Nonetheless, the element works flawlessly. One more thing is that the naming convention for this element’s properties is a little bit odd, the author put everything in lowercase. (usually it’s in camelcase)