On initialization of the Grid the oDataString is correct, but when I apply a Filter (through the FilterMenu) or apply a sort to a Grid column the ToODataString extension method throws with null reference exception. If the FilterMode is set to FilterRow or revert back to 2.16.0 everything works as expected. 

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This bug extends to the functionality of the FilterMenu as a feature and is not connected only to the ToODataString();

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