Why does this react-bootstrap DropdownButton menu not properly load only on the first click?

I’m working on the Snow Today code repository over at https://nsidc.org/snow-today/snow-viewer and have run into a very confusing and frustrating bug.

When you load the map by clicking “Western United States” and click the “Select A Region” button, the dropdown menu does not initially load unless the button is clicked two more times, or you scroll on the page a little.

On the backend, the button is a react-bootstrap DropdownButton, but the weird part is that the rest of the buttons are also DropdownButtons, but do not experience this issue.

Does anyone have any insight to go about fixing this problem?