Highlight words in Select2

I am using Select2 and trying to highlight the found words during typing. For example I have created a new simple Input with class=“sel5”.
Now everything works fine.

Example, when I’m typing letter Bra in search box (input) with class=”sel5″, the word Brass highlights Brass in table.
One more example – when I’m typing letter Wate the word Water highlights Water

But I can’t do it for the class=“select 2-search__field” do the same effects as you can see in the example.
How can I get to the Input field?

Highlight words in Select2