UDataTableFunctionLibrary::AddDataTableRow() fails for blueprint-defined row structure types

The editor-scripting blueprint node "Add Data Table Row" fails when the Data Table uses a Row Structure that was defined in blueprint. Internally, it checks if the passed-in UScriptStruct is derived from FTableRowBase, which fails for type UUserDefinedStruct.

Replacing 

const bool bIsTableRow = RowType->IsChildOf(FTableRowBase::StaticStruct());

with

const bool bIsTableRow = FDataTableEditorUtils::IsValidTableStruct(RowType);

is a potential fix.

• Open UE 5.3
• Create a Blueprint Structure asset and add some fields
• Create a DataTable asset using that structure for its rows
• Create an Asset Action Utility to operate on DataTable assets. - Implement a function to get the selected DataTable and call node "Add Data Table Row" on it. Make a struct for the "row data" input.
• Right-click the DataTable asset and call the implemented ScriptedAssetAction on it.
• The output log will display a warning message, and the row won't be added