Resolve Twitter share button? The allowtransparency attribute on the iframe element is obsolete. Use CSS instead.

Hello,

 

When validating the site http://kalender2013.nl/ I get the following error:

Error Line 17, Column 5889: The allowtransparency attribute on the iframe
element is obsolete. Use CSS instead.

 

When looking at the issue I see this is generated from the Twitter button
with the following code:

<a href="http://twitter.com/share" class="twitter-share-button"
data-url="http://kalender2013.nl" data-text="Alle kalender in 2013!"
data-count="horizontal">Tweet</a><script type="text/javascript"
src="http://platform.twitter.com/widgets.js"></script>

 

This is the code from a default Twitter share button.

Is there anyway I can resolve the issue within the code?

 

Any comment would be appreciated.

 

Sam