In Revelation 5:8, what are the golden bowls full of incense?

Answer: The prayers of the saints

The living creatures and elders held harps and golden bowls full of incense, "which are the prayers of the saints."

“When He had taken the scroll, the four living creatures and the twenty-four elders fell down before the Lamb. Each one had a harp, and they were holding golden bowls full of incense, which are the prayers of the saints.”— Revelation 5:8 (BSB)