Returns the container ID of the currently focused container on C<$workspace>.
+Note that the container ID is B<not> the X11 window ID, so comparing the result
+of C<get_focused> with a window's C<< ->{id} >> property does B<not> work.
+
my $ws = fresh_workspace;
my $first_window = open_window;
+ my $first_id = get_focused();
+
my $second_window = open_window;
- is(get_focused($ws), $second_window, 'second window focused');
+ my $second_id = get_focused();
+
+ cmd 'focus left';
+
+ is(get_focused($ws), $first_id, 'second window focused');
=cut
sub get_focused {