Complex sentence: It was published in the spirit of a closet drama, intended to be read rather than staged, because of its complexity, length, and number of characters, places it depicts, and so no production of the play took place during Musset's lifetime.
Split into simpler sentences: It was published in the spirit of "Spectacle dans un fauteuil", and was intended to be read rather than staged. Indeed, because of its complexity, length, and number of characters and places it depicts, no production of the play took place during Musset's lifetime.