------------------- AI Summary -------------------

We upgraded Telerik UI for ASP.NET AJAX from version 2026.2.708 to 2026.3.812, with no changes to our navigation menu code. Our RadPanelBar menu is populated server-side via DataBind() using a SiteMapDataSource (no client-side population). Since the upgrade, clicking a menu item frequently does not navigate to its URL: the menu shifts vertically, the clicked item is not selected, and no navigation occurs. This is impacting customers’ ability to use our site.

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We are requesting assistance to troubleshoot and resolve this issue as quickly as possible. This problem is causing significant usability issues.

The panelbar item you click on selects the first root item of the panelbar, then changes to the actual selected item. This can be observed in the Custom Attributes demo.

You should, in general, use the ContentTemplate to provide content to items.

By original design and old documentation, the ItemTemplate must not be collapsible at all, but since it has been for ages, we must fix that to avoid a breaking change.

Items that have an ItemTemplate have the following collapse/expand issues:

    - they require two clicks to collapse for the first time
    - setting Expanded=false on the server keeps the ItemTemplate expanded
    - until you click their header they do not heave the coloring and expand/collapse arrow

See this changeset on how the templates should work and the change from the previous descriptions: https://github.com/telerik/ajax-docs/commit/67f0a252ff24e2397e042fe5797de3610a75221d which is available in the following article http://docs.telerik.com/devtools/aspnet-ajax/controls/panelbar/templates/overview

Please consider adding a ClientVisible or Display property to panel bar items that we can set server side to control the initial visibility of items on the client.

In the screenshot you can see the PanelBar and a menu to filter items to display. I like what I have except for the fact that I have to run javascript to filter items on each page load and async update based on the selected filter.

RadGrid has a property Display for columns which allows the column to be sent to the client but not be visible initially. I just want something like that for the PanelBar.

Thank you for your consideration.