Excessive GPU usage in ChatGPT Desktop on macOS when “Transparent sidebar” is enabled

What version of the Codex App are you using (From “About Codex” dialog)?

26.715.52143

What subscription do you have?

Pro

What platform is your computer?

Darwin 25.5.0 arm64 arm

What issue are you seeing?

With ChatGPT visible and the transparent sidebar enabled, measured GPU utilization was approximately 41–69%, often exceeding 60%.
The ChatGPT Chromium GPU helper also sustained approximately 16% CPU.
Hiding the ChatGPT window reduced total GPU utilization to approximately 12–20%.
Restoring the window caused utilization to return immediately to approximately 41–69%.
Disabling Transparent sidebar reduced GPU utilization significantly.
The Codex backend itself was nearly idle, so the load appears to originate from the desktop renderer rather than model computation.

What steps can reproduce the bug?

Open ChatGPT Desktop.
Select the Codex view and start a task.
Enable Settings → Appearance → Transparent sidebar.
Keep the ChatGPT window visible while the task is running.
Observe GPU utilization using macOS GPU statistics or Stats.
Disable Transparent sidebar without changing anything else.
Observe the GPU utilization again.

What is the expected behavior?

Displaying an otherwise mostly static task window should use minimal GPU. A translucent sidebar should not cause sustained GPU utilization above 60%, especially when there is only a small task-status animation on screen.

Additional information

Environment

ChatGPT Desktop version: 26.715.52143
Build: 5591
Embedded Chromium: 150.0.7871.124
macOS: 26.5.2 (25F84)
Hardware: MacBook Pro, Apple M4 Pro
GPU: 20-core integrated GPU
Memory: 24 GB
Display: Retina, 120 Hz ProMotion
App window: approximately 1244 × 891 points at 2× scale
App language: German

Additional diagnostic evidence

A stack sample of the ChatGPT GPU helper showed repeated:
Metal render passes and command-buffer commits
Core Animation layer commits
IOSurface composition
Chromium GPU-process activity
The app also contains continuously looping 60 fps task-status animations. The likely issue is that these small animations invalidate the translucent window composition continuously, causing the large Retina surface and sidebar blur/transparency to be recomputed at a high frequency.

Workaround

Disable:
Settings → Appearance → Transparent sidebar
Hiding or minimizing the ChatGPT window also reduces GPU usage, but disabling sidebar transparency allows the app to remain usable.

Impact

Increased power consumption
Reduced battery life
Additional heat
Potential fan activity and reduced performance in other GPU-intensive applications