macOS Tahoe: Dock icon rendering bugs (pixelation, gray boxes)

Hi everyone,

After updating to macOS Tahoe 26 (25B78), I’ve encountered several Dock issues:

  • Dock icons appear pixelated (especially at small sizes).
  • Third-party app icons get placed inside gray boxes (“icon jail”), making them harder to recognize.
  • Custom folder or app icons are sometimes replaced with generic ones.
  • Icon and widget themes can mismatch when switching between light and dark mode.


Steps to reproduce:

  1. Update to macOS Tahoe 26.
  2. Add third-party apps or custom folders to Dock.
  3. Resize the Dock or use an external monitor.
  4. Activate/deactivate screensaver or switch display modes.
  5. Switch between appearance themes.


What I’ve tried:

  • Restarting the Dock via Terminal (killall Dock)
  • Restarting my laptop twice

Is anyone else seeing this? Any solid workarounds? Appreciate any help or insights!


MacBook Air 13″, macOS 26.1

Posted on Nov 6, 2025 8:58 PM

Reply
12 replies

Nov 11, 2025 4:51 PM in response to dialabrain

Thanks for checking. It may be size/session‑dependent.

On macOS 26.1 (25B78), I can reproduce at small Dock sizes.

Exact settings when it breaks (in my case): tilesize=24, magnification=1, largesize=26 (built‑in display on Default for display; also repro on an external).

I’ve attached two captures taken minutes apart — Bad shows pixelation/aliasing, Good is crisp.

If you try the exact values below and still don’t see it, it may be model‑specific or session‑specific.



defaults write com.apple.dock tilesize -int 24
defaults write com.apple.dock magnification -bool true
defaults write com.apple.dock largesize -int 26
killall Dock


Current reads here:


tilesize=24
magnification=1
largesize=26

Nov 11, 2025 4:23 PM in response to hnrie

Same here on macOS 26.1.


Dock icons look pixelated/aliased at small sizes and sometimes “fix” themselves after a few reboots, then come back.


Setup: built‑in display set to Default for display; also reproducible on an external monitor.


tilesize=24, magnification=1 (On), largesize=26.


Tried: reset Dock prefs (defaults delete com.apple.dock; killall Dock), IconServices/cache clears, toggling Reduce Transparency/Motion. Safe Mode didn’t change it.


Looks like a 26.1 rendering/scale regression at small sizes.

Nov 11, 2025 5:15 PM in response to dialabrain

Fair point about the slider. I only quoted exact values because the glitch seems to live in a narrow size band.

On 26.1 I can repro at the small end. If you nudge the slider to roughly 10-15% from the left (and optionally a tiny magnification), you may see the same aliasing. I’m not saying “people should use 24 px”; it’s just that the bug only shows in that tight range, so exact numbers make it reproducible.

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

macOS Tahoe: Dock icon rendering bugs (pixelation, gray boxes)

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.