Dynamic contextmenu items cause null exception in ContextMenu.positionSubmenu

[greg9504]

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Plunkr Case (Bug Reports)
Please demonstrate your case at stackblitz by using the issue template below. Issues without a test case have much less possibility to be reviewd in detail and assisted.

Here is stackblitz with 13 and failing:
https://stackblitz.com/edit/angular-ivy-fa7of2?file=src/app/app.component.html

Here is stackblitz with 10 and working (please ignore url naming):
https://stackblitz.com/edit/angular-10-directive-elementref-example-ws5lg4?file=src/app/app.component.ts

Current behavior

Dynamically add items to bound MenuItem[] then use ContextMenu.show(). First time you are able to select the dynamically added menu item. The dynamically added item is removed in the onHide() event. The second time you right click the dynamic item is added again but a null exception occurs. This was working fine with Primeng 9 and 10. When updating to 11 the bug was introduced, and exists in 13.

Expected behavior

Not throw null reference exception.

Minimal reproduction of the problem with instructions

See above.

Please tell us about your environment:

Windows 10

• Angular version: 5.X

Bug first appears with Angular 11, but present in 12 and 13.

• PrimeNG version: 5.X

Bug first appeared with Primeng 11, present in 12 and 13.

• Browser: [all | Chrome XX | Firefox XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]

Only tested with Chrome Version 98.0.4758.82 on Windows

• Language: [all | TypeScript X.X | ES6/7 | ES5]

• Node (for AoT issues): node --version =
  With or without IVY.

[greg9504]

thank you for looking at this.