I have done some work recently on trying to make Emacs work conveniently
under any circumstances when started via emacsclient.

I have been trying to replicate the model of single-instance applications
like Firefox and Libreoffice (because Emacs is naturally single-instance),
where running the command when the application is not running will start a
new instance, and otherwise, will start a new window in the existing single
instance.

Using the "nearly-default" setting of empty ALTERNATE_EDITOR is pretty
good, but the trouble is that "emacs --daemon" does not do X session
support, so if I happen to start Emacs that way, I can then log out and
back in and find that all my windows have disappeared, whereas if I started
Emacs normally, it would save all my windows and their positions.

I can see there are reasons why a daemonised Emacs might not be able to
support X sessions (for example, if it's started without access to the
user's X display), but it would be nice if "emacs --daemon" supported the X
session if it was able to, as then one could always use "emacsclient",
knowing that if there wasn't a regular running Emacs, one would get one,
and that in most cases (hopefully predictably!) it would DTRT.

Am I overlooking some reason why this is hard to arrange? If this worked, I
would run "emacs --daemon" at X startup, to guarantee that it would be run
in the "right" context.

-- 
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