Fix intermittent invalid state error in loadfile (cli) (#4642)

* Fix intermittent invalid state error in loadfile (cli)

* Found the rootcause

Author: haslinghuis

src/js/tabs/cli.js

@@ -100,6 +100,9 @@ cli.initialize = function (callback) {
     self.cliBuffer = "";
     self.startProcessing = false;
 
+    // Reset modal dialog reference since DOM gets rebuilt on tab switch
+    self.GUI.snippetPreviewWindow = null;
+
     const enterKeyCode = 13;
 
     function clearHistory() {
@@ -159,6 +162,7 @@ cli.initialize = function (callback) {
                 );
                 $("#snippetpreviewcontent a.confirm").click(() => executeSnippet(fileName));
             }
+
             previewArea.val(result);
             self.GUI.snippetPreviewWindow.showModal();
         }

src/js/utils/initializeModalDialog.js

@@ -54,11 +54,15 @@ export function initializeModalDialog(activationSelector, dialogSelector, messag
         onClose && onClose();
     });
     // Handle activation button click
-    $(activationSelector).on("click", () => {
-        dialogElement.showModal();
-        // Reset any previous scrolling
-        dialogContainerElement.scroll(0, 0);
-    });
+    if (activationSelector) {
+        $(activationSelector).on("click", () => {
+            dialogElement.showModal();
+            // Reset any previous scrolling
+            if (dialogContainerElement) {
+                dialogContainerElement.scroll(0, 0);
+            }
+        });
+    }
     // Return dialog element
     return dialogElement;
 }