I saw Petula Clark on Broadway in BLOOD BROTHERS. We were at the Music Box Theatre sitting on house left, so we could see into the stage left wings. During one scene, I noticed Ms. Clark standing in the wings next to a small red light. She was holding a rolled up rug in her arms.
The scene changed, the light turned green, she walked out onstage, unrolled the rug, sang a song, the lights changed, she rolled up the rug and walked out, stage right.