The only possible action with the FilterOperations enumeration is to remove items from it during the FilterOperatorsLoading
event. Adding new FilterOperations is impossible because there is no way of knowing if the new operation will work correctly.
What you can do is to create a custom filtering control, however this means that you will have to implement the filtering logic too. You can see this blog post
and this article
in our online documentation both of which explain how to create a custom filter.
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