Hello guys and girls bought my first Audi A7 just before Christmas. It's a 2012 A7 s line
Now I was removing the boot/trunk trim and noticed a bit of plasti on the floor and when I looked . I seen it was on the back window at some point. I don't know if I knocked it off or ii it was done when the windows got tinted in the past. But anyway I looked around and could not see any wire hanging loss and there was not wire on the fitting. So I'm a little lost.
Anyway I sanded the back down added some solder and put it back on the window.

Now anyone have any idea what it could be

I don't know how to add pictures but thanks for any help