Add parent checking before inserting or removing the child

public/js/flutteringRibbon.js

@@ -3,7 +3,7 @@ const idFlutteringRibbon = 'canvasFlutteringRibbon'
 
 function destroyFlutteringRibbon() {
   const ribbon = document.getElementById(idFlutteringRibbon)
-  if (ribbon && ribbon.parentNode) {
+  if (ribbon && ribbon.parentNode && ribbon.parentNode.contains(ribbon)) {
     ribbon.parentNode.removeChild(ribbon)
   }
 }

public/js/nest.js

@@ -109,7 +109,7 @@ function createNest() {
 
 function destroyNest() {
   const nest = document.getElementById(idNest)
-  if(nest && nest.parentNode){
+  if (nest && nest.parentNode && nest.parentNode.contains(nest)) {
     nest.parentNode.removeChild(nest)
   }
 }

public/js/ribbon.js

@@ -80,7 +80,7 @@ function createRibbon() {
 
 function destroyRibbon() {
   const ribbon = document.getElementById(idRibbon)
-  if (ribbon && ribbon.parentNode) {
+  if (ribbon && ribbon.parentNode && ribbon.parentNode.contains(ribbon)) {
     ribbon.parentNode.removeChild(ribbon)
   }
 }

public/js/sakura.js

@@ -165,9 +165,11 @@ function createSakura() {
   function stopp() {
     if (staticx) {
       var child = document.getElementById(id)
-      child.parentNode.removeChild(child)
-      window.cancelAnimationFrame(stop)
-      staticx = false
+      if (child && child.parentNode && child.parentNode.contains(child)) {
+        child.parentNode.removeChild(child)
+        window.cancelAnimationFrame(stop)
+        staticx = false
+      }
     } else {
       startSakura()
     }
@@ -177,7 +179,7 @@ function createSakura() {
 // 销毁樱花雨
 function destroySakura() {
   const sakura = document.getElementById(idSakura)
-  if (sakura && sakura.parentNode) {
+  if (sakura && sakura.parentNode && sakura.parentNode.contains(sakura)) {
     sakura.parentNode.removeChild(sakura)
   }
 }