Cannot link item to Chromecast Artist channel with PaperUI

Using PaperUI, I have added lots of items to channels of the Chromecast thing but it does not work with the Artist channel.

I tried “new item” and an existing item, but after I click “Link”, it is not linked.

Using openHAB 2.4.0.

Hardware setup?
OH version?
Java version?
Binding version?
Your binding settings?
What have you found regarding this on the forum?
Did you read the binding docs?

Hardware setup? Linux
OH version? 2.4.0
Java version? Java™ SE Runtime Environment (build 1.8.0_192-b12)
Binding version? 2.4.0
Your binding settings? ???
What have you found regarding this on the forum? Nothing
Did you read the binding docs? Yes

I also raised logging level for the Chromecast binding and binding in general to DEBUG but saw no extra messages when the binding of the channel to the item fails.

What else can I do to debug this?