How many letters does the top answer for “wrote a midsummer night's dream” have?

The most common answer is mendelssohn (11 letters).

Crossword clue: wrote a midsummer night's dream

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

mendelssohn 11 letters wd-fact-v3

German musician and romantic composer of orchestral and choral works (1809-1847)

shakespeare 11 letters wd-fact-v3

English poet and dramatist considered one of the greatest English writers (1564-1616)

author of a midsummer night's dream 60% similar → mendelssohn, shakespeare

composer of a midsummer night's dream 60% similar → britten, mendelssohn