Splitbutton commands not triggered when using keyboard

[blackholegalaxy]

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[x ] bug report => Search github for a similar issue or PR before submitting

Repro Case (Bug Reports)
No need for template, issue on official demo page.

https://www.primefaces.org/primeng/splitbutton

Current behavior
When using tab navigation we can open the split button menu. Then we can navigate through menu items. using Enter keyboard key works well for links (because we have href attribute). But for items with a custom command => () as update or delete in the official demo page, item is not triggerable using keyboard. This can cause serious accessibility issues.

Expected behavior
We expect custom command to be triggered while using keyboard navigation for accessibility purpose.

Minimal reproduction of the problem with instructions
Go on demo page, go to first split button using tab key. Open the menu with enter or space key. Then tab to "Update" or "Delete". Hit enter -> nothing happens. The event is only triggered using click.

What is the motivation / use case for changing the behavior?
Accessibility. Prevent usage of the button for people using keyboards.

Please tell us about your environment:
All

• Angular version: 13

• PrimeNG version: 13.4.0

• Browser: all

• Language: TS