Screenshots of windows include the shadow
Feature summary
When GNOME Shell or GNOME Screenshot are used to capture a window (not a region nor a screen), the resulting captured image should not include the shadow, or at least have an option. The current behaviour of including the shadow goes against the window capturing capability, users wanting the capture for documentation purposes will need to open an image editor and remove the border, that will be the same work that capturing the entire desktop and then cutting the windows from there, or to always use the area based screenshot tool and then using an editor to fix the not perfectly done area selection (specially on HiDPI screens)
How would you like it to work
Window screenshots should have no shadow included.
There was a discussion at gnome-screenshot#116 (closed) where the problem is depicted as being generated by the shadows being client generated. Unless the shadow generation is moved server side and this allowing all toolkits to have the same kind of shadow (currently doesn't for example Blender has a smaller shadow than GNOME, Dosbox has no shadow and so on). If the shadow continues to be client generated, then the client should draw to two different surface, one for the shadow and another for the window content, and the server composite them for the screen, and use only the content one for the screenshot.
Relevant links, screenshots, screencasts etc.
Example (green fill added later in order to make the border visible on the issue):