The “menu at the top of the screen” is just one possible visualization.

Essentially an application that supports this can “export” its menu so that it can be consumed by another process.

In the case of the “global menu” this is Plasma (applet).

However, the data can also be consumed for example by a window decoration plugin, like this one https://discuss.kde.org/t/decoration-with-locally-integrated-menu/29492

There are likely many more possibilities. Maybe a Kwin effect that shows the menu as a circle of options around the mouse cursor’s current position.

Strange video description. Contains advertisement for Proton Drive which does not even have a Linux client or any form of KDE integration

Welcome to KDE Plasma land 😀

I am particularly happy that you’ve mentioned activities! 😁

They are a somewhat under appreciated (or misunderstood?) feature that I personally find invaluable and it is great to see someone else feeling the same way