bug#40817: 27.0.91; setting frame parameter '(left - 0) leaves gap to the right under GTK

[martin rudalics]

> I see this with the GNOME shell on Ubuntu 20.04 (not sure if itʼs
> using mutter, how does one check that?).

With the task manager.  With wmctrl it identifies itself as GNOME shell.

> However, the good news is that the behaviour is correct using the
> pgtk build, including '((top - 0)).

Good to hear.  I haven't had time to look into this so far but I always
hoped that a pure GTK build would solve this and maybe some of our other
GTK issues.  It would be interesting to know whether and how the
arguments of

        gtk_window_move (GTK_WINDOW (FRAME_GTK_OUTER_WIDGET (f)),
                         f->left_pos / scale, f->top_pos / scale);
in xterm.c and

    gtk_window_move (GTK_WINDOW (FRAME_GTK_OUTER_WIDGET (f)),
                     f->left_pos, f->top_pos);

in pgtkterm.c differ.  BTW, did you test this with X11 or Wayland?

martin