SteamVr plugin showing blue gradient background... (Vive)

I came back to an old project and with my horror I discovered that the camera was not working after the latest update. It always showed a green/bluish background gradient.
Controllers can't be seen in the HMD but in the unity scene all the CameraRig gameobjects are there and move accordingly.
I tried everything I could think of, and later I tought I messed with some project configs, so I closed everything and started a blank new project just to look if it could work .
I Reimported the latest Steamvr plugin, opened the Steamvr_TestTrackedCamera scene and the problem still persist.
Games and the steamvr dashboard are fine, I can't figure whats going on.

Anyone has an idea of what in the world is happening?

EDIT: I just discovered the SteamVr composer must be in fullscreen mode for some reason... that fixed it.
I never changed that before.
hope it helps.