Things that happen using jquery-2x and don't happen using 1.7.2

Things that happen using jquery-2x and don't happen using 1.7.2

Hi all!
I have a div tag fixed positioned in lower left part of the page.
It works perfectry using jquery-1.7.2 and 1.8.3(also 1.6.4).
But when using jquery>1.9.1.....to the "edge, it disappears.
Looking  in the Firebugs, it shows "element.style" and "display:none". I have never wrote inline style.
I searched in css,js,html...all posible thing that could affect to this div.
But I could not see why. The page is long one, so I cutted less than 10% of page and copied and pasted in fiddle. It also happens.If I change the vesion of jquery to 1.7.2, works fine. but using >1.9.1,do not.
The div only have one function(toggle) that auments the size of paragraph, 2 lines of code. And it's called "letraG", an ID of this div that has a pragraph "zoom".
If anyone could watch where is the problem....I'll grad it very much.
Thank you.

p.s 1: The script is in: http://jsfiddle.net/Masahiro/6uPtU/#&togetherjs=5EOV7sTzh3
p.s 2: The div#letraG is at the line 9 in HTML,
                                  at the line 70, 83(hover) in CSS,
                            and at the line 21 in JS.
p.s 3: The version of the jQuery is now, 1.7.2, so you can see the div#letraG in the left bottom part fixed.