MultiSelect - v19, itemcheckboxicon template not being picked up

[tgfactor]

Describe the bug

After numerous attempts, and confirming that the headercheckboxicon template is indeed working, for some reason the multiselect component is not picking up the itemcheckboxicon template.

The header:

The regular checkbox:

Pull Request Link

No response

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://stackblitz.com/edit/bdtm3gtb?file=src%2Fapp%2Fmulti-select-template-demo.html

Environment

Using Primeng 19.0.6, attempting to use font-awesome icons.

Angular version

19.0.6

PrimeNG version

v19

Node version

No response

Browser(s)

No response

Steps to reproduce the behavior

Simply add the template for itemcheckboxicon and headercheckboxicon, include anything, it will show in the header but not in the items.

Expected behavior

I would expect to see the checkbox icon next to each item replaced with my appropriate icon in the template.