How to show additional properties in panel

In the example properties panel there are different tabs in the panel besides General (Listeners, Input/Output etc.).
In the example properties panel extension these are not there, instead a new tab is created manually.

My question: Why are they displayed in the first example? They do not seem to be explicitly configured (as far as I can see), but I cannot seem to find which setting / code is responsible for these extra tabs.

Hi @Adrian,

they are displayed in the first example because we use an existing properties provider, which is adding those tabs.

For the extension example, we create a new, customized provider.

Thanks for the explanation!