Re: Changing default mouse bindings

[Yuri Khan <yuri.v.khan@gmail.com>]

On Tue, Nov 14, 2017 at 9:50 AM, Stefan Monnier
<monnier@iro.umontreal.ca> wrote:

>> Drew mentioned that this context menu is shown only on mouse release in
>> Windows,
>
> Sounds like a bug.  I'd expect that it's easy to fix (tho I admittedly
> have no experience with Emacs under Windows).

No, that sounds like a feature. In general, showing the context menu
on a mouse up makes it possible to perform several different gestures
of varying complexity:

* Simple secondary click: mouse down, followed by a movement not
exceeding a few pixels, followed by mouse up. This normally just shows
the context menu.
* Secondary drag-select: mouse down at a position A in text buffer,
followed by a movement across buffer text to another position B,
followed by mouse up. Normally selects a region spanning from A up to
B and shows the context menu applicable to it.
* Secondary drag-and-drop: mouse down within a marked region, followed
by movement to a position outside the region, possibly in a different
window, frame or application, followed by mouse up. Shows a menu that
offers multiple actions that could be done to the region and the
target position (move or copy text between buffers; move, copy, hard-
or symlink files across the file system; feed text or file as input to
a program).
* Mouse gestures: mouse down, followed by movement in a well-defined
geometric shape, followed by mouse up. The action performed then
depends on the shape of movement.

(Firefox 57 is scheduled to be released today. There is much wailing
and gnashing of teeth over not being able to use mouse gestures any
more because on GTK3/GNU/Linux and macOS the context menu pops up on
mouse down and the new extension model does not allow extensions to
override that.)