Question: What occupation did Modest Mussorgsky and Carl Maria von Weber share?

Context articles: Die drei Pintos
Hochschule für Musik Carl Maria von Weber
Clarinet Quintet (Weber)
Symphony No. 1 (Weber)
Wiener Carneval
Bassoon Concerto (Weber)
Silvana (opera)
Carl Maria von Weber
Euryanthe
Modest Mussorgsky

Die drei Pintos ("The Three Pintos") is a comic opera of which Carl Maria von Weber began composing the music, working on a libretto by Theodor Hell.
 The work was completed about 65 years after Weber's death by Gustav Mahler.
The "Carl Maria von Weber" College of Music (Hochschule für Musik "Carl Maria von Weber" in German, and also/formerly known as Dresden Conservatory or Dresden Royal Conservatory) is a college of music in Dresden, Germany.
The Clarinet Quintet in B♭ Major, Op. 34, is a clarinet quintet that was composed by Carl Maria von Weber from 1811 to 1815.
 Like with most of Weber's other clarinet compositions, the quintet was written for the German clarinet virtuoso Heinrich Baermann.
Carl Maria von Weber's Symphony No. 1 in C was written in 1806–1807.
 While not usually acknowledged as among Weber's greatest works (a fact readily admitted by Weber himself), it is a testament to the young composer's gift of melody.
Wiener Carneval ("Viennese Carnival"), opus 3, is a waltz composed by Johann Strauss I in 1828.
 The waltz was intended as a contribution to the carnival of 1828 Johann Strauss appeared as leader of a group of musicians at the balls at the Kettenbrücke in Leopoldstadt.
 The fourth waltz theme incorporates melodies from Carl Maria von Weber's Ocean aria from Oberon, with Rezia’s words "Mein Hüon, mein Gatte, die Retter, sie nah’n" ("My Hüon, my husband, the rescuers approach"), partly as a tribute to Weber, who had died not long before Strauss' waltz was composed.
Carl Maria von Weber's Concerto for Bassoon in F Major, Op. 75 (J. 127) was composed in 1811 for Munich court musician Georg Friedrich Brandt, and then revised in 1822.
 Primarily an opera conductor and composer, Weber had only arrived a few months earlier in Munich, where he was extremely well received.
 The concerto is one of two pieces written for bassoon by Weber, the other being "Andante e Rondo Ungarese", Op. 35 (J. 158).
 A typical performance lasts 18–20 minutes.
Silvana, J. 87, is an opera by Carl Maria von Weber, first performed in Frankfurt am Main on 16 September 1810.
 The libretto, by , is a reworking of an earlier, unsuccessful opera by Weber, "Das Waldmädchen ".
 Weber also reused music from the same piece in "Silvana".
Carl Maria Friedrich Ernst von Weber (18 or 19 November 1786 5 June 1826) was a German composer, conductor, pianist, guitarist and critic, and was one of the first significant composers of the Romantic school.
Euryanthe is a German "grand, heroic, romantic" opera by Carl Maria von Weber, first performed at the Theater am Kärntnertor, Vienna on 25 October 1823.
 Though acknowledged as one of Weber's most important operas, the work is rarely staged because of the weak libretto by Helmina von Chézy (who, incidentally, was also the author of the failed play "Rosamunde", for which Franz Schubert wrote music).
 "Euryanthe" is based on the 13th-century romance ""L'Histoire du très-noble et chevalereux prince Gérard, comte de Nevers et la très-virtueuse et très chaste princesse Euriant de Savoye, sa mye.""
Modest Petrovich Mussorgsky (Russian: Моде́ст Петро́вич Му́соргский ; ] ; 21 March [O.S. 9 March] 1839 – 28 March [O.S. 16 March] 1881 ) was a Russian composer, one of the group known as "The Five".
 He was an innovator of Russian music in the romantic period.
 He strove to achieve a uniquely Russian musical identity, often in deliberate defiance of the established conventions of Western music.