It looks like you might have activated Trace & Reference.
Open the T&R palette and you can turn the trace off with the top left button.
ALT+F2 is the keyboard shortcut on Windows.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11