Saving HTML in text confirmation causes error

I am trying to place a Facebook like box at the end of my forms "text" confirmation message. I have auto formatting disabled so I should be able to add my own HTML, including javascript, correct?

Every time I do this and hit the save button I get this error:

There was an error while saving your form. Please contact our support team.

the html I am trying to place:

<div class="fb-like-box" data-href="https://www.facebook.com/hyperma" data-width="292" data-show-faces="true" data-colorscheme="dark" data-stream="false" data-border-color="white" data-header="false"></div>

Can anyone guide me here? I really need to get this working for an event that's taking place tomorrow.

Thanks

David,

Moving to single quotes did the trick. I'm a little embarrassed I didn't think of that myself.

As for the "Data" I presume it's because the new Facebook widgets use HTML5 and data attributes are a part of the html5 spec?

Either way, I didn't write the code i only used the widget creator on the Facebook dev site and that is the code it pumped out.

Thanks again for your help.