suggestion: Use requestAnimationFrame instead of window.onresize.

In some of my personal apps, I've noticed that making an animation loop with requestAnimationFrame and detecting window size inside there then updating stuff seems to be smoother than relying on window.onresize (https://github.com/sfirrin/Clean-Google-Calendar/blob/master/main.js#L37).

An example: https://infamous.io/

On desktop, try resizing with the mouse back and forth. The layout (the content at the bottom) is generated with JavaScript that is hooked in by requestAnimationFrame.

By the way, awesome Chrome app! 😃