diff --git a/app/desktop/book.go b/app/desktop/book.go
index e560c1a1d..655824669 100644
--- a/app/desktop/book.go
+++ b/app/desktop/book.go
@@ -21,7 +21,7 @@ import (
 //go:embed content
 var Book embed.FS
 
-const VERSION = "5.2.0"
+const VERSION = "5.2.1"
 
 func main() {
 	port := flag.Int64("port", 8080, "port for listen and serve example 8080")