Fix double #codefund div

Prevent the creation of a double div with the id codefund

Author: PicchiKevin

index.js

@@ -15,11 +15,13 @@
     },
 
     injectCodeFundContainer() {
-      let nav = document.getElementsByClassName('sidebar-nav')
-      let codefundContainer = document.createElement('div')
-      codefundContainer.id = 'codefund'
-      nav[0].insertBefore(codefundContainer, nav[0].firstChild)
-
+      if(document.getElementById("codefund") === null){
+        let nav = document.getElementsByClassName('sidebar-nav');
+        let codefundContainer = document.createElement('div');
+        codefundContainer.id = 'codefund';
+        nav[0].insertBefore(codefundContainer, nav[0].firstChild);
+      }
+      
       if (document.getElementsByClassName('cf-wrapper').length === 0) {
         window._codefund && window._codefund.serve();
       }