It is possible to override the FilterCell template in a way similar to the one shown for the FilterCell operators at:
However, with this approach, using the public API only, you will override all
the FilterCell templates, not just the template generated for type string(the Kendo UI NumericTextBox, DatePicker etc. will be gone as well):
There are two ways to achieve the global override of some data types and not others - one would require overriding a private method which will not be subject to support and may be changed in the future.
The other one is to wrap the Kendo UI Grid and make your own jQuery plugin based on it. This way you may specify how the filter cell template should be generated.
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