> Who defines what's special and what's normal though? Typical app does not need to touch its window decoration, only some need. The distinction is natural. Ev

> Who defines what's special and what's normal though? Typical app does not need to touch its window decoration, only some need. The distinction is natural. Even Gtk+ knows that distinction and lets you disable CSD for apps that don't customize the header bar. > Because of Xwayland and interactions with the user? Because it's tightly related to the whole DE, even more than under X, and that DE already has a toolkit for the compositor to use, be it Gtk+, Qt, Evas, St or whatever else. Plus, interactions. Plus, XWayland.