Our app does not work in React StrictMode

see: 40238bf

For example when StrictMode is enabled the maps context menu no longer works and the positioning of the custom model editor is broken.

I think the reason the context menu does not open in strict mode is that the context menu listener is removed here:

graphhopper-maps/src/layers/ContextMenu.tsx

Line 55 in d376677

map.getTargetElement().removeEventListener('contextmenu', openContextMenu)

but it is only added via the map.once('target:change') callback here:

graphhopper-maps/src/layers/ContextMenu.tsx

Line 39 in d376677

map.once('change:target', () => {

Since StrictMode runs the useEffect multiple times the listener is removed but not added again. And the reason we add the listener in this strange way, is that the useEffect is called for the map before it has a target element. Maybe we should do this another way, but currently I don't really know how. The target element is attached here at the moment:

graphhopper-maps/src/map/MapComponent.tsx

Line 14 in d376677

map.setTarget(mapElement.current!)