Can you please confirm what do you mean by mentioning customer cell: a custom CellEditTemplate, a custom column, or a custom cell class that inherits from GridViewCell (GridViewCellBase)? I tested the described behavior with the latest official binaries that we provide and it seems that it works as expected. I am attaching the test project that I used. Please have a look and share what are the differences with your project, so that we can pinpoint the issue more easily. Here is the test video
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