I knew of it, because I have Kobbé's Complete Opera Book and have read most of the summaries at one time or another*, though I don't think I've ever heard the music...

I do love the idea of Rodolfo singing "an entire aria explaining the theory of sleepwalking".

* If you ever want a really preposterous tragic plot, try La Wally, whose title is an apt description of the contents of the tin, but which does include the very well-known aria used (though fortunately shorn of context) in the film Diva, if you remember that.