That brings the area at the bottom right of the panel to just say the current Activity.

It is also the widget I am using, mostly as an indicator on which activity I am on.

Switching happens almost exclusively with shortcuts :)

I think the panels are currently not affected by activities, i.e. they remain the same across activity switches.

Applets on the desktop, wallpaper, etc seem to be per-activity

That explains absolutely nothing…

It explains the question of "why do they make this".

What’s changed is a compatibility layer.

Much more than that. What has changed is that studios explicitly work towards compatibility with it.

Are you saying there’s going to be a compatibility layer for iOS apps or something?

Well, there are already those for Android.

Wouldn't be surprising if someone did the same for Tizen or any of the other vendor's SmartTV systems. They all Linux systems after all.

Also this is only an issue for some proprietary apps. Some of which are often just fancy frontends for services which are also accessible in a web browser.

The people working on this might not even be using those

I vaguely remember having that on a new user account that I created for a demo.

I think what I did back then was to go to about config and set browser.tabs.drawInTitlebar to 0

Not just window position. Also size, which screen, which virtual desktop, which activity, state (maximized, etc)

Probably just replacing "KF5" with "KF6" in the cmake file and changing the version from "5.90" to something like "6.0" (or higher)

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