[dmitriid]

Polymer only uses browser facilities at the most basic level. As soon as you get into data binding/data passing/callback/events, Polymer becomes ... weird.

Still my favorite one is "Commas in literal strings: Any comma occurring in a string literal must be escaped using a backslash (\)." here: https://polymer-library.polymer-project.org/3.0/docs/devguid...

React is Javascript through and through, and yes, it only uses browser facilities. Because JSX is not custom tags, it's function calls: https://reactjs.org/docs/react-without-jsx.html