Multiselect: fails to automatically scroll to the first selected item

[rosenthalj]

Describe the bug

The PrimeNG p-multiselect component does not automatically scroll to the first selected item when the multuiselect's dropdown is opened.

This worked in v17

The first video shows the current PrimeNG v19 multiselect group demo not working.

v19MultiselectAutoScrollBad.mov

The second video shows the current PrimeNG v17 multiselect group demo working properly

v17MultiselectAutoScrollGood.mov

Note: I chose the multiselect group demo because the basic demo doesn't have enough option items

Pull Request Link

#17322

Reason for not contributing a PR

• Lack of time
• Unsure how to implement the fix/feature
• Difficulty understanding the codebase
• Other

Other Reason

No response

Reproducer

https://primeng.org/multiselect#group

Environment

n/a

Angular version

18

PrimeNG version

v19

Node version

n/a

Browser(s)

all broswers

Steps to reproduce the behavior

1. Start the PrimeNG v19 multiselect group demo: https://primeng.org/multiselect#group
2. Using the dropdown Select the city Kyoto
3. Reopen the dropdown
   -- the city Kyoto is selected, but the dropdown has not scrolled to Kyoto

Expected behavior

Repeat the steps using the PrimeNG v17 demo: https://v17.primeng.org/multiselect#group
-- the city Kyoto is selected and the dropdown scrolls to th Kyoto