JavaScript runtime error: Object doesn\'t support property or method \'registerElement\'
in File: ... bower_components\\polymer\\polymer.js Line 11701
Currently only Chrome and other blink-based browsers support Custom Elements. Firefox supports but not enabled by defualt.
See Can I Use for a full supporting chart.
If you are using it on other browsers, you need to include a Web Components polyfill (usually a file named webcomponents.js).