RenderTexture destroyed when device changes state?

Unity Engine
1

At the startup of a level, I use a render texture to save a background image. If I switch the screen resolution to full screen after that, that texture will be destroyed and I’ll see a weird sample texture there instead. Do all rendertextures get blown away when the device state is lost and regained? Is there any way to preserve them?

2

Has anyone else tried using rendertextures? Do you normally refresh them every frame - IE should I not be saving a render?

3

This: http://forum.unity3d.com/threads/87860-Lost-Graphics-Device fixes it for me (as long as you have the ability to recreate).

So I just do this:
void OnApplicationFocus()
{
if (!m_OriginalTexture.IsCreated())
{
Debug.Log(“Recreating background”);
StartCoroutine(FixTextures());
}
}