Annoying ghosting bug resolved after i've added this: HKLM\SOFTWARE\Microsoft\Windows\Dwm \ OverlayTestMode = 5

No i couldn’t resolve it with gpu performance switch, reinstalling the fonts, re installing the illustrator and ect….
Seems like adding the option above is the only solution for the ghosting bug.
 

Title: Ghosting / stale text repaint in Illustrator — fixed by disabling Multi-Plane Overlay (MPO)

Body:

I want to share a fix for a rendering issue in Illustrator, in case it helps others running into the same thing.

The problem

When typing text in Illustrator, sometimes the words I typed wouldn't show up on screen. I could only see what I'd written by toggling the layer off and back on, which forced a repaint. I also got general ghosting — stale repaint artifacts left on the canvas.

What I tried that didn't work

• I found suggestions that this is a common issue and can usually be fixed via the GPU Performance option (turning it off). That didn't work for me.
• I then found some faulty fonts and repaired them. This fixed the issue temporarily, but after a while it came back.

What actually fixed it

The root cause turned out to be Multi-Plane Overlay (MPO), a Windows DWM feature — not strictly an Illustrator bug. Disabling it via the registry was the only thing that permanently resolved the ghosting and the missing-text-on-screen problem for me.

Add this DWORD and restart (a full reboot, not just sign out — DWM needs to re-initialize):

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Dwm]
"OverlayTestMode"=dword:00000005

To revert, just delete the OverlayTestMode value and reboot.

Two notes

1. NVIDIA driver updates tend to wipe this key, so the ghosting may return after a driver update. Just re-apply the .reg file and reboot.
2. On Windows 11 24H2 and newer, OverlayTestMode=5 may no longer reliably disable MPO. If that's your case, add a companion 32-bit DWORD named OverlayMinFPS set to 0 in the same Dwm key, then restart.

Hope this saves someone the hours I spent chasing fonts and GPU settings.