Mode line menus

[Chong Yidong <cyd@stupidchicken.com>]

Currently, the menus accessible from the mode-line (e.g. by clicking on
the major mode name) are bound to down-mouse-1.  Therefore, you have to
hold down the mouse button after clicking the menus.  Releasing the
mouse button immediately dismisses the menu, selecting the item the
cursor was on (if any).

My understanding is that this behavior is nowadays extremely
non-standard.

Nowadays, clicking on a menu button is expected to pop up a menu, which
is dismissed by clicking elsewhere or by selecting a menu item with
another click.  In Emacs, this can be accomplished simply by binding the
menus to mouse-1 rather than down-mouse-1.  (This works for both GTK and
non-toolkit builds).  The `mouse-appearance-menu' command, bound to
S-mouse-1, already makes use of this behavior.

Is anyone attached to the old behavior?  If not, I'd like to switch to
the standard behavior.