If I see a specific layer (eg. "2 Foot Contour") on the Layer List widget, what's the easiest way to programmatically find the layer by name and turn its visibility on/off.
Here are two threads you can consult:
Webapp Builder Layer List Widget
Make layer visible after LayerList widget has opened
This widget may be helpful:
Layer Toggle Button Widget Version 2.8 - 07/25/2018
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