Multiple TappablePolylineLayer and Gesture

[trauma-and-drama]

Hi all,
I have two TappablePolylineLayer included in a FlutterMap.
The problem: I get the mouse events only for the top layer, behaving opaque. I can't figure out why.
MapOptions has applyPointerTranslucencyToLayers=true per default. So it should allow all mouse events through all layers of its stack.

I changed the line for the GestureDetector to

// flutter_map_tappable_polyline:
  
Widget _build(BuildContext context, Size size, List<TaggedPolyline> lines) {
// ...
 GestureDetector(
        behavior: HitTestBehavior.translucent,
// ...

any idea is very much appreciated, because merging layers would be painful for my application's state management