Merge pull request #845 from chris-mrl/fix-crash-open-popout-navigation

check tabToRemove is not undefined before access

packages/dockview-core/src/dockview/components/titlebar/tabsContainer.ts

@@ -283,6 +283,9 @@ export class TabsContainer
 
         const tabToRemove = this.tabs.splice(index, 1)[0];
 
+        if (!tabToRemove)
+            return;
+
         const { value, disposable } = tabToRemove;
 
         disposable.dispose();