Hello
Many times when removing a TabItem manually, we need to update some parameter or trigger some event. I think this is a missing feature for the TabStrip Component and should be added as soon as possible. I made a Custom Version of the TabStrip and added this functionality (see the unrelined Lines below):
In TelerikTabStrip.razor.cs
        /// <summary>
        /// Fires when a tab has been removed.
        /// </summary>
        [Parameter]
        public EventCallback<int> TabRemoved { get; set; }  
void ITabContainer.RemoveTab(ICustomTab tab)
        {
  int tabIndex = Tabs.IndexOf(tab);
            if (PersistTabContent)
            {
                PersistedTabs.Remove(tab);
            }
            Tabs.Remove(tab);
  if (TabRemoved.HasDelegate)
                TabRemoved.InvokeAsync(tabIndex);
        }
This way we can handle the event of removing the TabItems manually and trigger additional actions.
What also could help is triggering the ActiveTabIndexChanged whenever a new TabItem is added or removed.
Thanks
BR
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