The IDs of the TabStrip content wrappers are based on the TabStrip ID with a hyphen and an index number as a suffix, e.g.
By knowing the index of the wrapper, which you want to access, you can modify its content.
Alternatively, you can use unique custom CSS classes for the content wrapper divs, which (unlike custom IDs) are preserved during the widget initialization, so you can use them in jQuery selectors.
All the best,
the Telerik team
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