If we revert we loose iron-list's keyboard focus. I would rather fix any issues and move forward. 

Resizing the window makes the list contents appear. I am pretty sure that this is an iron-list behavior which we've encountered before. IIRC if the iron-list is not explicitly sized, then it shows no contents on first load.

Potential fixes
1) Change this back to a dom-repeat instead of iron-list, 
2) Manually fire a 'resize' event,
3) Figure out why the list is not explicitly sized (more info at https://github.com/PolymerElements/iron-list#sizing-iron-list).

If we do (1) we have to work out another option for keyboard focus, plus we loose some of the benefits of iron-list for large lists.

There is supposed to be an explicit call when the list changes already, but in other places we've need to do something more robust, it is probably time to generalize that pattern.

I believe this is fixed now.