Parallax freezes page

I am trying to set a parallax background image to the widget Social Profile. After updating the page freezes. I only see a white screen with bouncing balls. What could be the problem?

I just made a reset wordpress database and import the demo content Sydney theme. In a rows “DO YOU WANT TO …” and “WHAT OUR CLIENTS SAY” set the background image with the effect of parallax. It really looks great, but I do not understand how image added into row? If I try to create a row with background images in parallax mode, my front page are freeze after updating.

I realized my mistake. It is necessary to set a background image in a edit row, not edit widget.