I tried to reproduce the behaviour that you described in this on-line demo
but to no avail. The grid configuration used in the demo seems to be similar to yours - there is a detailTemplate with a TabStip inside it. Can you reproduce the issue in it? If not could you please provide a small example that isolates it? In this way I would be able to examine your current implementation in details and assist you further. I will appreciate if you also specify if the problem occurs in a specific browser or not.
Thank you in advance for the cooperation. Looking forward to your reply.
the Telerik team
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