Insecure content warning when loading jQuery Drag / Drop function from Dropbox

I have created a simple page with a drag and drop feature. When I open the html file directly from my machine, everything works fine, however, when I try to share the html through linking to the public folder on dropbox (trying to embed it on another page, for example) the drag and drop features won’t work - although all other functionality is still there - this is the message I’m getting:
Any ideas?

To fix this, load jQuery by using this protocol:

https:// (not http).

Dropbox public pages are accessible over HTTPS, so if you load insecure content, Safari will throw an exception for non http content loaded in iframes.

Many thanks Daniel, much appreciated.