Thanks for contacting the Syncfusion support.
We have checked the reported issue by specifying the string to the CustomContextMenuItem property. From the latest version 22.214.171.124, we need to use the CustomContextMenuItem property as List of objects instead of List of strings and in the Grid definition we need to define the Id, Text pair of inner level property in ContextMenuSettings. So, we have considered “Not able to access CustomContextMenuItem property in inner level property of ContextMenuSettings” as an issue and a support incident has been created under your account to track the status of this requirement.
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