The overview is one of the defining features of GNOME 3, and thus
almost by definition at odds with the classic session, which
emulates a traditional GNOME 2 desktop.
Even with the less prominent placement inside the application menu
it never quite fit in - it doesn't help that besides the different
UI paradigma, the overview keeps its "normal" styling which differs
greatly with classic's normal mode.
So besides removing the "Activities" button via the session mode
definition, now that the apps-menu extension doesn't replace it anymore,
disable the overview completely in the classic session.
https://gitlab.gnome.org/GNOME/gnome-shell-extensions/merge_requests/69
Per-desktop overrides aren't limited to keys in org.gnome.mutter, so
we can use them instead of the alternate-tab extension to default to
the window switcher in the classic session.
https://bugzilla.gnome.org/show_bug.cgi?id=786496
GSettings now recognizes per-desktop overrides that can be used
to change schemas' default values for classic mode, so use that
instead of the separate override schema we currently use with
mutter's custom override mechanism.
https://bugzilla.gnome.org/show_bug.cgi?id=786496
Meson has a strict separation of source- and build directory, and
expects anything generated in the latter. That means that in order
to maintain our current setup - shipping the generated CSS in the
repo while also optionally updating it automatically when sassc is
found - we have to fight the build system to some extent, which makes
it less reliable than we would like.
Since we switched to sassc which is a more acceptable build-time
dependency than the original ruby-based tool, just drop the CSS
from the repo and unconditionally generate it from SASS if classic
mode is enabled.
https://gitlab.gnome.org/GNOME/gnome-shell-extensions/merge_requests/28
Most buttons appear in modal dialogs which keep their normal
appearance in the classic theme, except for the calendar's
"Clear All" which needs a dark text color to be readable on
the light background.
https://gitlab.gnome.org/GNOME/gnome-shell-extensions/issues/26
GTK+ switched from ruby-based sass to c-based sassc for performance
reasons. It makes sense to follow suit, if not to not require two
tools for the same job ...
https://bugzilla.gnome.org/show_bug.cgi?id=783210
