Dropping an image to desktop opens a finder window

Hi all,
I don’t know for sure if it’s caused by TotalFinder, but here it goes…
If I drag and drop an image from browser (Chrome Version 30.0.1599.69) to desktop,
a finder window pops-up, showing the desktop contents.

Does anyone know this is a normal behavior caused by a setting in a(ny) preferences?
Thanks in advance for your attention/reply.

Mountain Lion 10.8.5
TotalFinder 1.5

Anyone has an idea why/how could this happen?

I don’t want a finder window to open when I drag/drop an image to the desktop from (Chrome) browser.

It happens for me too and only when using Chrome, Safari doesn’t have the same problem. Have not tested any other browser. Rather annoying as I mostly use Chrome.