The launcher does not update the status of the selected version after installing it (even after restarting the launcher).
I noticed this issue and thought that it could be an issue with my mods and whatnot, so I completely deleted my .minecraft folder and reinstalled (using the new dev launcher). Everything installed fantastically, but it still does not recognize that I have the selected version installed.

Steps to reproduction:
1. Install vanilla Minecraft via any method
2. Use the Dev Launcher to open Minecraft
3. Install any version using the Dev Launcher
4. Close all open Launcher or Minecraft windows and reopen the Dev Launcher
5. The Dev Launcher will say that the just-installed version "Will be installed"
5b. (It actually won't be installed again- it "Used own copy as it matched etag")

Proof below: followed steps above, navigated to correct folder to witness that I legitimately had the correct version installed but that it still shows that it "Will be installed."