The wmanagerrc-update program creates or updates the ~/.wmanagerrc file with a list of X11 window
managers currently installed on the system. On systems that do not have a convention for registering X
window managers, wmanagerrc-update simply copies the contents of the ~/.wmanagerrc.user file to
~/.wmanagerrc.
On systems that register the installed X window managers, the wmanagerrc-update program adds all of them
to the wmanager(1) configuration so that they are available soon after installation. Currently, only
Debian GNU/Linux and similar systems that use the update-alternaties(8) mechanism are supported. Locally
installed window managers and things not registered as alternatives for x-window-manager(1) can be added
to the file ~/.wmanagerrc.user in the .wmanagerrc format; see the wmanager(1) README file, usually
/usr/share/doc/wmanager/README.gz, for more information. The wmanagerrc-update program uses the entries
first from ~/.wmanagerrc.user, then from the the registered window managers, in the order of
update-alternatives(8) priorities. You can override this by listing entries in wanted order in
~/.wmanagerrc.order, separated by whitespace.