This UI glitch with the timer overlaying the crosshair is annoying.
Some people with custom huds are having this issue but not all of them have the timer in the same spot. I don’t have the issue with my hud but my friend does. So there is definitely a setting that is screwing up at some point. You can also try setting it up the way you want and setting the file to read only as that might fix it.
My text chat is like in the upper left hand corner, blocking the objective HUD. But somehow OP, you hit a lot of headshots with that bug, idk if that timer overlay kinda gives you a broad reference for having you fit the enemy’s head in that box than shoot.
I still have a green x-hair, also basic knowledge of the center of my screen helps too 
I have this bug, highly annoying.
-Switching teams seems to fix it.
-Switching from Spectator to a team also seems to fix it.
-After a few minutes it fixes itself.