[Violation] Long running JavaScript task took 211 ms

[dman777]

Description

paper-menu-button causes chrome warning [Violation] Long running JavaScript task took 211 ms

Browsers Affected

• [x ] Chrome
• Firefox
• Safari 9
• Safari 8
• Safari 7
• Edge
• IE 11
• IE 10

I've narrowed down my code to this paper-menu-button causing this warning:

        <paper-menu-button>
          <paper-button class="dropdown-trigger" raised>
            <iron-icon icon="visibility"></iron-icon>&nbsp&nbsp
            <span>View By</span>
          </paper-button>
          <paper-menu id="viewMode" class="dropdown-content" 
             selected="0">
            <paper-item>foo</paper-item>
            <paper-item>foo</paper-item>
            <paper-item>fooe</paper-item>
            <paper-item>foo</paper-item>
            <paper-item>fooage</paper-item>
            <paper-item>foo</paper-item>
          </paper-menu>
        </paper-menu-button>

If I remove this, the warning goes away.