The most notable baroque innovation was the development of "drama through music," which we now call

The answer is: Opera

Explanation:

Opera, previously known as drama through music, is a part of the Western classical music tradition. It is a theater or staged drama in which music has the leading role and the various parts are taken by the singers and is accompanied by a small musical ensemble or an orchestra. An opera performance includes acting, costumes, scenery, and sometimes ballet or dance.

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