I'm looking through the ESRI StoryMap Team collection of Storymaps for 2019 put together by Hannah Wilber -- Specifically looking at (Farm) Animal Planet:
https://storymaps.arcgis.com/collections/9d81757581bb4be68ce8de1510bbf923/present?item=1
Using Safari 13.05 (Mac desktop, OSMohave 10.14) the map in the Sidecar remains static.
It doesn't change while the text scrolls by (I think there are about 6 slides?) I cleared Safari cookies and tried again. Nada.

I opened Chrome to view the same StoryMap - there is no problem with Chrome -- the map densities change accordingly.
Is this is Known Issue with the ArcGis StoryMap Sidecar -- but only when using Safari?
Mia