How can I change the Render Regions background display mode? I regularly use the handy Render Regions feature of Blender, but I have noticed that no matter what mode you are in before entering Render mode, the background mode for the parts of the scene outside the lines is always solid. I want to know if there is a way to change that to Textured mode. 

Here is an example of what I mean. I am in Texture mode, with a render region set up.



However, when I enter rendered mode the plane on the right loses it's texture, and is now completely solid, obviously being displayed in Solid mode.



Is there a way to change this behavior? And if not, what workarounds are there?
Sadly, this appears to be impossible*. 

*Blender is open source, you could always add the feature ;D (I mean isn't that the whole point of open source)