svg draw using append does not work

Hi all,

I also find that the current git version does not work on using svg drawing.
In annotationTools/js/plot.js, there are lots of draw functions, such as DrawPolygon, DrawPolyLines, ... all of these functions use $('#'+element_id).append("xxx");
However, it does not work at my side. By "not work", I mean these functions show no output on my screen. I use console.log to check what was contained in $('#'+element_id), and found that the append does not work.

So, I googled, and find a workaround by adding

var divName = String('#'+element_id+'_div');
if (divName != null) $(divName).html($(divName).html());

these two lines at the end of each these draw function.
It generally works, but I cannot believe this is the right way to go.

My question is that
is there any special setup I should follow?

My environment is macbook pro + safari/chrome, apache 2.4.

yours,
Luming