A <form> element inside a <template> element will cause the next form element to be removed from DOM in all latest versions of Safari. As you can see in the demo, the <form> element is removed while the form's content is still visible. If you comment out the <template> element, the form displays correctly. Demo: http://codepen.io/achisholm/pen/eBxjyX?editors=1100
*** This bug has been marked as a duplicate of bug 158386 ***