displayed sometimes failing oddly

[bennypowers]

I'm using chai-dom to check if elements in my Polymer app are hidden:

<style> [hidden] {display: none !important} </style>
<section id="activity" hidden$="[[someProp]]"></section>

test('Activity view should be hidden by default', () => {
  testView.someProp = true;
  testView.$.activity.should.not.be.displayed;
});

output:

chrome 59                ✖ test/eve-activity.html » eve-activity basic tests » Activity view should be hidden by default

  expected section#activity to not be displayed, but it was as
    <unknown> at   Context.test at eve-activity.html:45:0

[nathanboktae]

Looks like you opened two issues for the same thing (#22).