Starting a radio does not clear the queue.
UI/UX is inconsistent in some cases. One of such cases is playing an album, track or playlist. When user does so, it clears the queue and enqueues the desired thing by default. However when it comes to radios, when we start a radio, the radio tracks are being enqueued without clearing previous queue.
Although we already have an issue that is titled exactly the same, this issue is about inconsistency in the UX rather than a bug. If you read through #343 (closed), you can conclude that this behavior is desired and by design. In my opinion in somewhat hurts the UX and should be changed.