Dropdown ScrollTop

[Emilio Amado]

Hi folks,I need some help with Bootstrap dropwon element. 

I'm developing a calendar component, when I display a "bootstrap dropdown" whit the years, I'm trying to set the vertical scroll bar of the dropdDown to a specific position when it's opened. When I open the dropdown for the first time, I want to scroll the bar to the position of the element that shown in the "years" button.

As you can see in the following picture, the first time that I open the dropdown, I displaying the "2020" value in the button element, but the scroll It's in the top position:

What I want is set the position of the scroll bar to the "2020" year position.

This is the complete code:
https://jsfiddle.net/wx31qjvk/

I tried to use "scrollTop" in the "hlCurrentYear()" function without success.

Thank you very much for your help

Greetings, Emilio.

[Carlos Alexandro Becker]

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