Calendar heat map is blank

[jlconlin]

I really like the idea of the calendar heat map. I tried to do the same thing with my blog, but it's not quite working for me. I downloaded the posts_heatmap_calendar.md file and placed it in my site. You can see (screenshot below) it mostly works… except for the important part. I'm using the excellent minimal mistakes theme.

I'm happy to debug this, but I don't even know where to start. I'm no javascript expert. Please advise.

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