Currently, running on desktop requires overriding the default target platform using a debug flag. From previous discussions, before we add desktop platforms to TargetPlatform we need to audit the framework for a list of significant changes we would want to make for desktop (e.g., button and text field metrics, scrollbar behaviors, etc.), and have a plan to burn that last down fairly quickly. The goal is to minimize the amount of time where behaviors are changing, so there's not time for people to start depending on behaviors that are then changed.

Filling to track that overall project.

CC @gspencergoog