In some areas, there are large polygons (e.g. landuse), they may mask smaller polygons (e.g. buildings). Sometimes, it is not possible to select the smallers ones because the touch event is captured by the bigger polygons.
This behaviour is unfortunately usual in web maps...
As a workaround, we could enable polygon selection when the user choose "box selection" mode. Not completely satisfying though...
In some areas, there are large polygons (e.g. landuse), they may mask smaller polygons (e.g. buildings). Sometimes, it is not possible to select the smallers ones because the touch event is captured by the bigger polygons.
Note: Initially reported by Jean-Louis Zimmermann