High WindowServer GPU usage on macOS Tahoe (same issue as Illustrator, fixed in Illustrator Beta 30.8.72)

Hello,

I am reporting this issue here following a suggestion from the Illustrator team.

I originally reported what appeared to be the same problem in the Illustrator UserVoice forum:

https://illustrator.uservoice.com/forums/601447-illustrator-desktop-bugs/suggestions/50552691-high-gpu-load-on-macos-26-tahoe

The Illustrator engineers investigated it and confirmed they found the cause. The issue is now fixed in the current Illustrator Beta (30.8.72), and I can confirm that the fix works correctly on my MacBook Pro M1 Max.

Unfortunately, Photoshop still shows the same behaviour.

Configuration

• MacBook Pro 16” M1 Max
• macOS Tahoe 26.5.2
• Latest Photoshop version

Observed behaviour

• WindowServer (not Photoshop) continuously uses a high amount of GPU while Photoshop is visible.
• Photoshop CPU usage remains low.
• GPU usage is proportional to the visible area of the Photoshop window.
• Minimizing or hiding the application immediately drops GPU usage.
• The behaviour is very similar to what was previously observed in Illustrator before the Beta fix.

Since the Illustrator team already identified and fixed a similar issue in their application, I hope these observations may help determine whether Photoshop is affected by the same underlying problem or by a similar one.

Thank you.