Re: mode-line highlight

[Masatake YAMATO]

> 1 - move mouse to one of the minor modes names on the mode-line.
>     press mouse-3 to get a menu of minor modes.
>     cancel the menu by releasing outside of it (while keeping the mouse
>     cursor pointing outside of any Emacs window): the mouse-face highlight
>     will be turned back ON (on the spot where you orignally pressed
>     mouse-3), even though the mouse is not in that area any more.
> 

I think it is nothing to do with mouse-line.
Please eval following code at *scratch*; and do the same on [PRESS ME] on 
your emacs with Lucid.

    (easy-menu-define test-menu global-map
               "Menu for `test-menu'."
               '("Test"
                 ["Gnus" gnus]
                 ["Grep" grep]
                 ))

    (let ((b (goto-char (point-max)))
          (e (progn (insert "[PRESS ME]") (point))))
      (put-text-property b e 
                         'mouse-face 
                         'highlight)
      (put-text-property b e 
                         'local-map
                         (let ((kmap (make-sparse-keymap)))
                           (define-key kmap [down-mouse-3] (lambda ()
                                                             (interactive)
                                                             (popup-menu 
test-menu)))
                           kmap)))

As Lute reported, emacs with Gtk+ behaves different way.
Ignoring this bug, I like the behavior of emacs with lucid; it shows the
association between a popup menu and its target item.
See smerge's popup menu behavior.

Masatake YAMATO