maputnik: Error messages lead to stuck/unchanging pop-up in Inspect view

I just upgraded to the latest Maputnik (from 1.4, I think). Since the upgrade, I get a stream of errors in my browser console after enabling Inspect view and mousing over the map. Here’s an example:

react-dom.development.js:558 Warning: Encountered two children with the same key, `transportation_name-undefined`. Keys should be unique so that components maintain their identity across updates. Non-unique keys may cause children to be duplicated and/or omitted — the behavior is unsupported and could change in a future version.
    in div (created by FeaturePropertyPopup)
    in FeaturePropertyPopup
warningWithoutStack	@	react-dom.development.js:558

I get a lot of these errors mentioning several of my map data layers. After mousing around briefly, the same handful of features is displayed in the Inspect pop-up no matter where I go on the map.

Anyone know how to fix this?

In case it’s relevant, I also get this error once:

Warning: Failed prop type: Invalid prop `value` of type `boolean` supplied to `StringInput`, expected `string`.
    in StringInput (created by FeaturePropertyPopup)
    in FeaturePropertyPopup
printWarning | @ | checkPropTypes.js:20