bug#25851: 25.2; GTK warning when starting Emacs when desktop file has more than one frame

[N. Jackson]

At 10:46 +0100 on Tuesday 2017-02-28, martin rudalics wrote:

>> Rather that trying to cover up the warning, can we not just do what the
>> library wants; is it impossible for us to call "gtk_widget_show_all() on
>> the contents and gtk_window_set_geometry_hints() on the window" before
>> calling gtk_window_parse_geometry()?
>
> Did you try?  I suppose that gtk_widget_show_all would introduce some
> additional flicker.

No, sorry, I didn't try. This is my first glimpse of any of the Emacs
window management code, and I'm not familiar with the GTK. Is there
documentation anywhere giving an overview of this area of Emacs? For
example, the "Commentary" section in frame.el is empty.

The question above was simply from a higher-level perspective. It looks
like we're not using the library in the way it is designed to be used,
so I assumed that there must be a reason why we are not. And I wondered
if that reason might not be worth reconsidering.

As for additional flicker, when I start Emacs things jump about like a
scalded cat, including a phantom random vertical scroll bar that often
makes a momentary appearance in the middle of my display. I've never
really understood why Emacs does this then other programs seem to manage
without such problems, but I've come to accept the behaviour -- after
all, it's only momentary while Emacs starts up -- and I don't think
additional flicker would necessary be much worse!

N.