While we do not have subwindows in Wayland, we do create an
artificial root window. When the display is closed, the root
window gets destroyed, causing recursing to be true for the
toplevel windows.
Since being 'activatable' istead of 'button' now that reset
is not needed anymore, the patch is pretty noisy since sass
interpreter changes, those look innocuous though.
A * selector applies to all widgets, so even GtkBox or GtkGrid - and
most importantly GtkListBoxRow - need to recompute their style because
of the * selector.
By using a more specific one, these common cases aren't affected
anymore.
Fixes slowdowns in gtk3-demo's listbox demo and in gnome-software.
That way, the GTK engine doesn't think that the general .button CSS
might potentially apply to it.
And because combobox button is overly complex and stupid, it cannot be
cached.
So buttons thought they cannot ever cache anything because they might
suddenly end up inside a combobox without noticing and then they'd need
to round their corners differently. Of course they're just regular
"Remove" buttons like all the other 100s of "Remove" buttons in
gnome-software. But hey, better not cache anything for them and
recompute their CSS every time the :hover state changes on one of the
rows.
We can actually share :first-child/:last-child related things now,
because we special case them. So the only positions we cannot cache are
nth-child/nth-last-child.
This should take care of a lot of Adwaita's styling.
This example populates a flow box with buttons, and makes the
flow box children unfocusable, with the intention that the focus
moves directly between the buttons. Currently, keynav does not
work at all in this case.
This way, we can live without row references.
A side effect is that opening the inspector on the gtk-demo list box
example now only takes 0.5s instead of the previous 3 minutes.
Instead of queueing a new idle handler every time we call
gtk_window_update_debugging(), only queue one if none is queued that.
Saves a lot of work, in particular when templates create context menus
for every row in a large listbox as in the gtk-demo listbox example.
Do not use .button anymore.
This is for 2 reasons:
1. The styling is seperate in our themes, so it doesn't make sense to
share the style class.
2. Due to the shared styling of .buton, listbox rows inherit all the
special case styles that exist for buttons - such as linked buttons,
header buttons, entry buttons, spinbutton buttons, etc. This means
that the code has to check all these special cases all the time and
for listbox rows, this is very slow.
Defer a11y initialization until we have a display. A11y initialization
causes widget classes to be initalized, which in turn needs some
backend-specific information about modifier masks that can't be
obtained before we have a display.
https://bugzilla.gnome.org/show_bug.cgi?id=736125
