InDesign 18.3 - Ghost Stroke

[David302260236luh]

InDesign 18.3 — I'm using the Pen Tool to make a curved stroke. A strange fragment of that curve is showing up next to the one I draw. I have the Type set to solid. The fragment changes along with the settings I adjust for the stroke (weight, type...). I've attached a screen shot. What the heck is going on? 

[Eric Dumas]

Is it still appearing after zooming in -out?

From the View menu do you have: Overprint Preview on and Display performance to High Quality?

[David302260236luh]

Thanks for your reply. I have 25 years working with InDesign. I've never seen anything like this. Yes, it's still there when I zoom. Nor is it either of those other things. 

[Bill Silbert]

Try turning off GPU Performance in InDesign's preferences.