Help. Strange green square in Air combat

I haven’t played air for some time, and now I have this strange and very annoying green box. What is it, and how do I get rid of it?

It’s there both in RB and arcade.
I can’t play with that thing in the middle of the screen.

It’s a bug, although it only seems to effect certain planes, e.g the Finnish Hurricane.

Have you tried restarting your client? I’ve had a similar bug before, but not sure if it’s the same one here.

AGM visual field indicator persists after test drive

Thank you. Restarting the client fixed it.