Error when opening paper-menu in version 1.5.6

[BorntraegerMarc]

Description

The iron-dropdown component version 1.5.6 causes errors in the dev console when used together with paper-menu. This error results in that the whole app does not become scrollable anymore.

To reproduce

Expected outcome

Like in version 1.5.5 that no errors happen.

Actual outcome

The error happens:

Uncaught TypeError: Cannot assign to read only property 'target' of object '#<AnimationPlaybackEvent>'
    at b.Animation.<anonymous> (web-animations-next-animation.js:223)

Live Demo

Steps to reproduce

With this code:

         <paper-menu-button id="action-menu" vertical-align="bottom" style="padding: 0;">
            <paper-icon-button src="icon.png"
                               class="dropdown-trigger attachment-button"></paper-icon-button>
            <paper-menu class="dropdown-content" ignoreSelect="false">
                <paper-item click="addNewTask()">New task</paper-item>
                <paper-item click="addNewFile()">Attach file</paper-item>
            </paper-menu>
        </paper-menu-button>

Browsers Affected

• Chrome
• Firefox
• Safari 9
• Safari 8
• Safari 7
• Edge
• IE 11
• IE 10

[web-padawan]

The issue causing this is fixed, please update your bower dependencies.

[BorntraegerMarc]

@web-padawan I'm not using the web-animations-js dependency myself but only this component. Can I add a direct bower dependency in my bowe.json and it should work?

[web-padawan]

Yes, you can pin it to 2.2.2 or try using 2.2.4 which should work fine. Only 2.2.3 is broken.

[BorntraegerMarc]

@web-padawan Sorry, that did not work. I've tried with adding it to my bower.json and do a re-install:
"web-animations-js": "web-animations/web-animations-js#2.2.4"

Here's my full bower:

  "dependencies": {
    "app-layout": "PolymerElements/app-layout#0.10.6",
    "iron-flex-layout": "PolymerElements/iron-flex-layout#1.3.1",
    "paper-checkbox": "PolymerElements/paper-checkbox#1.4.1",
    "paper-styles": "PolymerElements/paper-styles#1.1.5",
    "paper-icon-button": "PolymerElements/paper-icon-button#1.1.3",
    "polymer": "Polymer/polymer#1.8.0",
    "iron-icons": "PolymerElements/iron-icons#1.1.3",
    "paper-button": "PolymerElements/paper-button#1.0.14",
    "paper-dialog": "PolymerElements/paper-dialog#1.1.0",
    "paper-input": "PolymerElements/paper-input#1.1.20",
    "paper-card": "PolymerElements/paper-card#1.1.4",
    "paper-toast": "PolymerElements/paper-toast#1.3.0",
    "paper-item": "PolymerElements/paper-item#1.2.1",
    "paper-ripple": "PolymerElements/paper-ripple#1.0.10",
    "paper-avatar": "Abe90/paper-avatar#1.0.2",
    "paper-menu-button": "PolymerElements/paper-menu-button#1.5.2",
    "paper-dialog-scrollable": "PolymerElements/paper-dialog-scrollable#1.1.5",
    "vaadin-upload": "1.1.1",
    "iron-collapse": "PolymerElements/iron-collapse#1.3.0",
    "font-roboto": "PolymerElements/font-roboto-local#1.0.1",
    "web-animations-js": "web-animations/web-animations-js#2.2.4"
  }

[BorntraegerMarc]

@web-padawan I am experiencing this issue again when I updated all my dependencies to Polymer 2.0. Have you also experienced this issue again in Polymer 2.0?

[BorntraegerMarc]

BTW: The warning in the console disappears when I add the import <link rel="import" href="assets/bower_components/neon-animation/web-animations.html"> manually but the scroll issue persists. So it breaks my app at the moment...