subsurface side channel between plasma and kwin and applet. keyword: "IVI shell"
popups: plasma creates another window gives it to kwin and the applet
focus handling is a challenge. needs cooperation of applet. plasmashell can definitely claim focus when it is sure it needs to have it
For the Plasmoid attached properties we could have generic interfaces for read/write properties. writable may require an allowlist for what is writable.
