[OS X Emacs] Re: Aquamacs 2.1: transient-mark-mode going berserk on me

[Christian Kirsch]

Erik L. Arneson schrieb:
> On Thu, 30 Sep 2010, Christian Kirsch wrote:
>> I'm using Aquamacs 2.1 on Mac OS X 10.6.4. The editor is now quite often
>> going into some kind of automatic transient-mark-mode: I position the
>> mouse somewhere in the text and click to move the cursor to this
>> position. If I then press <down> (without shift!), the whole text
>> between the last mouse position and the new cursor position is
>> highlighted.
> 
> This happens very frequently for me, too, except that it's typically
> after I have highlighted a region using C-SPC and the arrow keys.  After
> C-w (kill-region), the mark is still active about 95% of the time.  Not
> every single time, though.  I am not sure what causes it.
> 

Right, after I posted to the mailing list, I was more attentive: Seems
that the behavior is related to first selecting something via C-SPC
followed by arrow key.

In this weird "mode", M-< even highlights the whole buffer :-(

> This also happens frequently to me when I hit page-up/<prior> (fn-<up
> arrow> on my MacBook).  That runs command `aquamacs-page-up'.  Note that
> the mark doesn't get activated *every* time, though.  Just about 15% of
> the time with page-up/<prior>.
> 
>> It behaves as if I had marked marked it with S-<down>. I
>> can temporarily turn off the highlight with C-g, but if I move point
>> again with one of the cursor keys, I get highlighted text again.
> 
> I don't know how to fix the bug, but if you use C-SPC it will unset the
> mark and you'll be back to normal.
> 
What I'm doing now is C-G C-SPC C-SPC to turn-off the hightlight and
then set/remove the mark.

> 
> I have no idea, sorry.  It happens to me, too.

Since we're two at least, may be it will be considered a bug rather than
a feature ;-)