If you select an airway leg in a flight plan, it appears that in 8.43.1 db95b8a, the first segment that exists in the airway’s definition gets selected instead of the particular airway leg.
A simple reproduction is the route RSK V421 DRO; after loading the route into Charts (I’ve tested Windows, Android, and web), if you click/tap the airway segment between the navaids (either on the map or on the route widget), the segment of V421 between ZUN and GUP (a small distance to the southwest) gets selected instead, as that segment is listed first in the list of V421’s segments.
The expected behavior is to select the particular airway segment being represented by the particular leg of the route, which would also be a useful behavior as it allows checking what course the airway follows at each end (which can be used to determine VOR radials, for instance).