diff --git a/app/src/layout/dock/index.ts b/app/src/layout/dock/index.ts
index 7952e3b13..983bacf9c 100644
--- a/app/src/layout/dock/index.ts
+++ b/app/src/layout/dock/index.ts
@@ -442,7 +442,6 @@ export class Dock {
         }
         this.layout.element.style.transform = "";
         this.layout.element.style.zIndex = (++window.siyuan.zIndex).toString();
-        this.element.style.zIndex = (++window.siyuan.zIndex).toString();
         if (this.position === "Left") {
             this.layout.element.style.left = `${this.element.clientWidth}px`;
         } else if (this.position === "Right") {