🎁 MacOS Sequoia compatibility - Unofficial Download Available

[PTriebold]

UPDATE:

Here is an unofficial build (source code available) that does not crash on macOS Sequoia:

https://github.com/waydabber/MonitorControl/releases/tag/v4.3.0-beta

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Original issue as follows:

Before opening the issue, have you...?

• [X] Searched for existing issues
• [X] Looked through the wiki
• [X] Updated MonitorControl to the latest version (if applicable)

Describe the bug

In the new Sequioa beta, MonitorControl will crash when setting the brightness of the internal monitor (16" Macbook). External Monitors work as expected.

Steps to reproduce

1. Update to MacOs 15 Beta
2. Change internal brightness trough MonitorControl

Expected behavior

The app changes the brightness of the internal display without crashing

Anything else?

I've tested it with a fresh install of monitorcontrol.
It actually changes the brightness of the internal monitor. If you disable the soft transition, it will be set to whatever was selected. It will get close otherwise.
Reseting the internal display also crashes monitorcontrol.

Environment Information (please complete the following information)

- macOS version: 15.0 Sequoia (24A5264n)
- Mac model: Macbook Pro (16-Inch 2021)
- MonitorControl version: 4.2.0
- Monitor(s): Internal, HP Z27k G3, HP Z27k G3
- Apple Silicon/M1 (yes or no): yes

[waydabber]

Here is a build with macOS Sequoia support:

https://github.com/waydabber/MonitorControl/releases/tag/v4.3.0-beta

[alextuan1024]

Thank you for your contribution. Does the volume control work fine on your monitor? It's not working on my LG.

[waydabber]

It should generally work, yes. If it doesn't, it might be a monitor issue. Or did it work before and not on Sequoia?

[alextuan1024]

Yeah it worked before, when the version was Sonoma. My best guess is the protocols are not very well supported on Sequoia.

[waydabber]

Are you on Intel or Apple Silicon? DDC should work fine (found no issues during tests). Does brightness control work?

[alextuan1024]

My device is a MacBook Pro with an M3 Pro chip, connected to an LG 27UP850 monitor, which also works as a power adapter via USB-C. Yes, the brightness control works fine. And I just found that the volume control works with the laptop cover open. But the volume slider disappears when I close the cover and only use the external display. If you need logs to debug, please lemme know.

[alextuan1024]

Not sure if this screenshot helps:

[waydabber]

Oh, all right, the problem is that when the lid is closed, your display is set to be in HDR mode. Sequoia made a change in HDR mode that confuses MonitorControl - the app treats it as an Apple display as it confuses Seqoia's new SDR peak brightness adjustment slider with a native brightness control which up to this point was only available for Apple (and some Apple-LG) displays and therefore turns DDC off.

It is probably not feasible to fix this in MonitorControl 4.x as a more fundamental change would be needed, which would kick-off a chain reaction me starting to rewrite/update the entire app due to its generally outdated nature... You can instead use the latest version of BetterDisplay in which this issue is already elegantly resolved + has all the features of MonitorControl for free (no license required).

[alextuan1024]

Thank you for the prompt response. I'll try it out later.