Animation error

[BorntraegerMarc]

Description

When adding the following code:

        <paper-menu-button id="actionMenu" vertical-align="bottom" #actionMenu>
            <paper-icon-button src="assets/imgs/plus-icon.png" slot="dropdown-trigger" class="dropdown-trigger attachment-button menu-trigger"></paper-icon-button>
            <paper-listbox slot="dropdown-content" class="dropdown-content menu-content" ignoreSelect="false">
                <paper-item class="menu-item mi-new-task komed-menu-item" (click)="addNewTask()">
                    {{'task.addTask' | translate}}
                </paper-item>
                <paper-item class="menu-item mi-new-file komed-menu-item" (click)="addNewFile()">
                    {{'chat.newFile' | translate}}
                </paper-item>
            </paper-listbox>
        </paper-menu-button>

And click on the button I get this warning in the console:

Couldnt play ( fade-in-animation ). ReferenceError: KeyframeEffect is not defined
    at HTMLElement.configure (fade-in-animation.html:39)
    at HTMLElement._configureAnimations (neon-animation-runner-behavior.html:33)
    at HTMLElement.playAnimation (neon-animation-runner-behavior.html:93)
    at HTMLElement._renderOpened (iron-dropdown.html:233)
    at HTMLElement.__openedChanged (iron-overlay-behavior.html:541)

And the whole page freezes.

Expected outcome

No error

Actual outcome

Live Demo

Steps to reproduce

Browsers Affected

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

[BorntraegerMarc]

Same error when adding <link rel="import" href="assets/bower_components/neon-animation/web-animations.html">

[BorntraegerMarc]

Saw that the issue lies else where. opened up https://github.com/PolymerElements/paper-menu-button/issues/125