proxy_license now raises ClickException instead of RemoteError (a SystemExit), so dl falls back to the track's vault key; licence messages name the track ("video 360p DV (592464997)").
Drop null keys from every licence, server and export source, not only Widevine. dl now finds remote sessions and imports through ServerKeySource instead of private fields.
A session above the cap licenses with the client's own device, and a track above it in an uncapped -q run is handed back to the client. Also names the fallback in the ccextractor crash warning.
A client with a local PlayReady device asked the server for a PlayReady licence on a service the server maps to a Widevine device. Both server_cdm routes now share one candidate list from one config lookup, report the system that licensed in drm_type, and the client adopts it.
imSp4rky