Hello colleagues.
Please tell me how to solve one issue pronounced in Firefox.
Having recently implemented a project on raphaeljs, I encountered the fact that when transferring an element with a mouse, you can touch the background and it turns out this effect:

This can happen as with a regular picture or with a picture inserted through the Raphael. This effect is brightly observed in firefox, in the others too, but less.
Tell me, is it possible to somehow prohibit this transfer for the browser.