Customization Form - Field list keyboard navigation is broken

Hello,
In the previous versions of the product, when we wanted to find a field name in the field list displayed when you right click in the filter area and select "Show Field List", we could use the keyboard to navigate in the field names.
Now it doesn't work well anymore. In fact, we can go to a field named 'Pxxxxxxx' by pressing "P" on the keyboard, but we cannot neither go to a field named 'Nxxxx' pressing "N", nor go to a field named 'Axxxxx' by pressing "A".
For some letters it works, and for some it doesn't.
Steps to Reproduce:
Create a PivotGrid with field having names starting by the different letters of the alphabet, in the data area.
Right click on the field area, select "Show Field List"
Try to navigate from field name to field name using the keyboard letters.
Actual Results:
For some letters navigation doesn't work
For others, it works as it used to in previous versions
Expected Results:
The navigation should be working for every letters
It would be even better if it could work for sequence of letters typed within a short time period