macOS 27 Beta 8: Built-in Liquid Retina XDR display ignores HiDPI scaling, resolution and XDR changes

[maximewohlgemuth]

Environment

Hardware

• MacBook Pro 14" (Apple M1 Pro)
• Built-in Liquid Retina XDR Display
• Native resolution: 3456 × 2234

Software

• macOS 27 Beta 8
• BetterDisplay 5.0.4 Internal

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Description

BetterDisplay detects the internal display correctly and exposes all available controls.

However, none of the following settings have any effect on the actual display:

• HiDPI scaling
• Resolution changes
• XDR / Display Headroom
• Extra Brightness

The BetterDisplay UI updates normally and settings are persisted, but macOS never applies the requested display configuration.

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Expected behaviour

Changing any display mode should immediately update the built-in display.

This includes:

• HiDPI scaling
• Display resolution
• XDR headroom
• Extra brightness

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Actual behaviour

The BetterDisplay interface behaves normally.

The selected values are saved.

No visible change occurs on the display.

The display always remains at the current macOS display mode.

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Reproduction

1. Launch BetterDisplay.
2. Select the built-in Liquid Retina XDR display.
3. Change HiDPI scaling or resolution.
4. Apply the change.

Result:

No visual change occurs.

The same happens with XDR / Extra Brightness.

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Verification performed

macOS Display Settings

Changing scaling directly from macOS System Settings works correctly.

Therefore:

• the display is functioning correctly;
• macOS is capable of changing display modes.

The issue only occurs when attempting the same operation through BetterDisplay.

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Clean installation

Performed:

• Complete BetterDisplay removal
• Preference reset
• Fresh installation
• Multiple reboots

No change.

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WindowServer

BetterDisplay successfully communicates with WindowServer.

Example log:

Display 1 setting display headroom hint to 1

This indicates BetterDisplay is sending display-related requests.

However, no display mode transition follows.

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CoreDisplay logging

Running:

log stream --predicate 'subsystem == "com.apple.CoreDisplay"' --info

while changing scaling or resolution from BetterDisplay produces no CoreDisplay events.

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Display information

system_profiler SPDisplaysDataType reports:

Display:

• Built-in Liquid Retina XDR Display
• 3456 × 2234 Retina

No abnormal configuration detected.

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HiDPI support

/Library/Preferences/com.apple.windowserver.plist

contains:

DisplayResolutionEnabled = 1;

Therefore HiDPI support is enabled.

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BetterDisplay binary

codesign reports:

Runtime Version: 27.0.0

The application is therefore built for macOS 27.

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Linked frameworks

BetterDisplay links against:

• CoreDisplay.framework
• DisplayServices.framework
• SkyLight.framework
• QuartzCore.framework

The application launches normally and detects the display correctly.

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Notes

The issue only affects BetterDisplay.

macOS Display Settings continue to function correctly.

Based on the observed behaviour, BetterDisplay appears able to detect the display and update its own internal state, but the requested display mode is never applied by the system.

If additional logging or testing is required, I would be happy to help.

[waydabber]

Hmm. I am not sure why this would happen - things seems to work fine here (16" MBP M3 Max) with the built-in display.

Can you try resetting the app (you can export settings and reimport them later) and reboot? You can also try resetting the system display configuration as well.

You can also check app logs to see what might be happening - expand the Tools menu, click Show Console and enable logging.