As @Jayesh correctly said, such feature is not supported out of the box. By default DataSource filters the underlying data, if the value of your date field contains time information, it will not be ignored.
The DataSource provides opportunity for defining a custom filter operator:
}, value: 10428 });
It would be easier to use this approach with external filter menu. The build-in one does not provide opportunity for customizing the operators like shown above.
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