Plugin conflict

Hi Guys,

I use the Enfold theme with great satisfaction. I’ve used the WP Simple Survey plugin on one page > http://www.mapwerkt.nl/quickscan/

This works fine, except for the last field of the survey > the Name & Email doesn’t show in Firefox. However it does work, cause it sends the email. It does show in Chrome and IE.

At first I thought it was a plugin-firefox conflict. But I’ve seen the plugin on other sites (http://www.ahealthylife.nl/test-je-gezondheidskennis-over-voeding/ ) and there the last Name & Email field is showing and working fine.

So I think it’s a conflict between either the theme or with one of the plugins. Any suggestions or help?