Vigilius Eriksen (1722-82) – Dowager Queen Juliane Marie of Denmark Kobenhavn (SMK) National Gallery of Denmark

The picture has something of this: people, woman, wear, veil, opera, portrait, dress, theater, castle, man, theatre, indoors, two, fashion, royalty.
Perhaps it’s a painting of a woman in a white dress and a tiara standing in a room with a blue curtain and green drapes on the wall.