Kendo React Grid Filter Issue with Turkish Characters "i"

[irfan]

I'm using Kendo React Grid (@progress/kendo-react-grid@9.1.0) with client-side filtering. One of my columns contains Turkish words like "CEVİZ" (with capital dotted İ, U+0130). I noticed a strange behavior when filtering:

• Typing "cevi" in the filter works correctly and returns "CEVİZ"

• Typing "ceviz" does not return any results

• Typing "CEVİZ" works

• Typing "iz" does not return results

• Similar issues happen with words like "SİDE" → "si" works but "sid" doesn't

It seems this is related to how JavaScript lowercases "İ" into "i\u0307" (with a combining dot), which causes unexpected behavior in includes() filtering.

I have lowercased to column data from "CEVİZ"  to "ceviz" before displaying but still have same problem. 

Questions:

1. Does the Kendo Grid's built-in client-side filtering normalize or handle Turkish casing (e.g., toLocaleLowerCase("tr"))?

2. Is there a recommended way to override or customize the string filtering logic to properly handle Turkish characters like İ?

3. If I provide a custom filter function, how can I ensure it's properly integrated for all relevant columns?

Thanks in advance!