diff --git a/internal/graphicscommand/command.go b/internal/graphicscommand/command.go
index 5ef686864..cff0669af 100644
--- a/internal/graphicscommand/command.go
+++ b/internal/graphicscommand/command.go
@@ -350,6 +350,8 @@ func (c *drawTrianglesCommand) String() string {
 		mode = "xor"
 	case driver.CompositeModeLighter:
 		mode = "lighter"
+	case driver.CompositeModeMultiply:
+		mode = "multiply"
 	default:
 		panic(fmt.Sprintf("graphicscommand: invalid composite mode: %d", c.mode))
 	}