I can't find how to change the basemap in crowdsourcing.
Hi -- there isn't a way to change the basemap within the Crowdsource builder, but you can just open the web map that the builder created and change the basemap there. The web map will have the same name as your story map and can be found on your Content page on arcgis.com.
Once you save the change to the web map, refresh your story and you'll see the new basemap.
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