The code of the window manager Mutter, developed within the GNOME 3.34 development cycle, , allows for the automated launch of XWayland when attempting to run X11-based applications in a Wayland-based graphical environment. The difference from the behavior of GNOME 3.32 and earlier releases is that previously the XWayland component would run constantly and required explicit prior launch (it was started during GNOME session initialization), but now it will be launched dynamically as needed for compatibility with X11. The release of GNOME 3.34 is scheduled for September 11, 2019.
Let’s recall that to ensure the execution of regular X11 applications in a Wayland-based environment, the DDX component is used (Device-Dependent X), which is part of the core codebase of X.Org. In terms of operation, XWayland resembles Xwin and Xquartz for Win32 and OS X platforms and includes components for running the X.Org Server over Wayland. The change made in Mutter will allow the X server to start only when necessary, positively impacting resource consumption in systems that do not use X11 applications in a Wayland environment (the process with the X server usually consumes over a hundred megabytes of RAM).
Source: opennet.ru
