Statistics - Graphs spin but don't draw

ISSUE:

The data graphs in Statistics do not render. They present a spinning circle and don't resolve. The same functionality works on the Sakai 11 nightly server but not Sakai 12 or Trunk.

STEPS TO REPLICATE:

• Create a site, make sure tools like Lessons, Resources, and of course Statistics are enabled
• Visit as one or more users. Click around. Do things.
• Go to Statistics.
• The area where the graph should display is simply a gray box with a spinning wheel at the top left corner.

Screenshot of what I see in Sakai 12.2 and Trunk in Firefox 60.0.2 Windows 10 and Chrome 67.0.3396.87.

Screenshot of what I see in Sakai 11.