Shuffle songs from different albums on Apple Music on a MAC?

I have the latest updates to both Apple Music and my 2019 iMAC (running macOS Catalina 10.15.7). For some reason I can no longer do the following:

Choose to play multiple albums by different artists, and have the songs shuffle. So if I had artists XYZ and their albums chosen, I would shuffle songs and Apple Music would play, say, Y,Z,Z,X,Y,Y,Y,XX for example.

I can do this on my iPhone, and I believe I could do this on my iMAC, but either I'm misremembering or something has changed because that functionality has to my eyes disappeared. I see the "shuffle" function on the dropdown menu, but it does nothing.

Any insights (no snark please) would be greatly appreciated.

(And, of course, I see this morning there is an update -- Big Sur -- which I will download, run and see what happens)