How many letters does the top answer for “author of the beggar's opera” have?

The most common answer is gay (3 letters).

Crossword clue: author of the beggar's opera

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

gay 3 letters wd-fact-v3

someone who is sexually attracted to persons of the same sex

author of the threepenny opera 50% similar → brecht

composer of the beggar's opera 50% similar → gay

wrote the beggar's opera 50% similar → gay