Definitely a bug as /u/DavidBraben said on the Stream, we hope we will have it fixed soon.
Unfortunately I don't know the magic key combo to get rid of it, but hopefully we can patch it out with a small patch soon.
Cheers, CMDR Falcon
No le deis más vueltas, es solo que se han olvidado de desactivar la mosca que te indica la versión y que suelen tener activada en las betas para saber rápidamente que build estás usando. Seguro que sacarán un hotfix en los próximos días que corrija eso y otros pequeños fallos que se vayan detectando en estos primeros pasos de Horizons.
This morning we have a quick update going out. The servers will go offline at 3PM UTC and will return within the hour. Below is the changes for this update...
Fix a render crash with schematics
Remove debug version string
Cannot target anything when in ship vicinity fixed
The following controls should now work when near a ship.
All other targeting buttons (cycling, next hostile, sub target, wings etc)
Cargo scoop lowering
Shield toggle and stabilize
Poll the state of module perks to notice when they go from No Effect to Available, and refresh the synthesis UI page
Allow Mac users to use Micro Resources that were previously gathered using their Horizons-enabled commander on Windows