Twitter card shows broken image in IE when site meta tag not provided


Our site does not currently specify the following meta tag:

<meta name="twitter:site" value="@halowaypoint" />

This field is not a required field but it looks like the Twitter website is placing the avatar image element on the page anyway, with src="". This seems to work fine in Chrome but IE thinks it should actually display an image and shows as broken. See this image:

I believe Twitter should not add this html to the page when twitter:site is not specified.

      <div class="CardAttribution">
        <a class="u-textInherit u-linkComplex js-openProfile"
          <img width="20" height="20" class="CardAttribution-avatar" src="" alt="">
          <b class="CardAttribution-name u-linkComplex-target"></b>

The alt tag on the thumbnail also seems to have a bug in it when twitter:site is not provided.

 <div class="CardContent">
            <div class="SummaryCard">
        <a class="js-openLink" href="" tabindex="-1">
    <img class="Thumbnail" src="" alt="View this content on 's website">

Here is a sample tweet: