Hi Luc,
WebRadio streams normally contain no coverart data.
France Music, Fip and Radio Paradise provide metadata and coverarts by their own
APIs.
For other stations, if the current playing song was found in
last.fm database, rAudio would get the coverart if available with an API for last.fm.
There's an issue with the scrobbler which run by
mpdscribble. Waiting for a fix.
rern