We have a section in Nuxeo for employee photos. These files are their own doctype contained in a custom, folderish doctype called "Library." For this Library, I have created a custom page provider with predicates and aggregates of schema fields relevant to these types of documents. I am having an issue with the filters for some of the fields though.
For example, every employee has an employee ID, so I have a schema/field for it called employee:employee_id (set as a string since IDs can contain letters or numbers). In the view of the parent container (Library) there is code to add a search filter in table view:
<nuxeo-data-table-column
name="Employee ID"
field="employee:employee_id"
sort-by="[[_displaySort(document, 'employee:employee_id')]]"
filter-by="employee_employee_id"
filter-expression="$term*"
flex="25">
<template>[[item.properties.employee:employee_id]]</template>
</nuxeo-data-table-column>
That field is a predicate in my custom page provider, with a full text operator. Here is the setup:

The issue I have is that for some IDs that all all numbers the filter works as expected and filters correctly as a user types in characters. However, for any of the IDs that start with letters the filter doesn't find anything at all. What could be causing this issue? I've tried different config settings, but I'm missing something (likely simple). Any guidance would be appreciated. Thanks.
I've attached a video demo of the search not working for an ID that starts with letters.
