PHP Call Hierarchy in Visual Studio Code?

I'm trying to figure out if there is a way to display a PHP classes structure within Visual Studio Code.

So if I have a class which consist of a constructor and 5 methods, I'm looking for a panel which lists that constructor and those 5 methods with the ability to jump to each one. I'm not looking for relationships to any particular symbol. I just want to know the structure of the class I'm working with.

The closest thing to this which I can find seems to only be for typescript, not PHP: https://github.com/microsoft/vscode-docs/blob/vnext/release-notes/v1_43.md#call-hierarchy-support-for-javascript-and-typescript

Note: I'm aware of the Go to "Definition|Type Definition|Implementations|References" in the context menu, but this is not what I'm looking for.

This is what the outline panel does. View -> Explorer to enable the Explorer panel, and then expand the Outline panel and just leave it open. It will automatically refresh based on what file you're editing and you can drag the top border to resize as desired.