<![CDATA[PySide6 UI looks different depending on which macOS built Python]]>If I built an app using macOS 15 using Homebrew Python (the exact version doesn't seem to matter, I tried several), then the app looks the same on macOS 15/27.

However, if I built it using Homebrew Python on macOS 27, then the app looks different (and in my opinion, worse).

Is there any way to force the old look?

This is the old look:
Screenshot_2026-10-27_at_3.21.13_PM.png

I got user feedback that the new look looks bad, especially with the pure white background.
Screenshot_2026-10-27_at_3.21.42_PM.png

]]>https://forum.qt.io/topic/165221/pyside6-ui-looks-different-depending-on-which-macos-built-pythonRSS for NodeThu, 05 Nov 2026 12:10:57 GMTWed, 28 Oct 2026 19:52:11 GMT60<![CDATA[Reply to PySide6 UI looks different depending on which macOS built Python on Fri, 30 Oct 2026 22:37:19 GMT]]>Is that white background different in other apps ?

]]>https://forum.qt.io/post/840700https://forum.qt.io/post/840700Fri, 30 Oct 2026 22:37:19 GMT<![CDATA[Reply to PySide6 UI looks different depending on which macOS built Python on Fri, 30 Oct 2026 03:33:59 GMT]]>Thank you, I missed that. I assume guidance has not changed for macOS 27 Tahoe.

Should I log feedback anywhere saying that the pure white background looks not great? I think that's the default? My users described it as "blinding"

]]>https://forum.qt.io/post/840687https://forum.qt.io/post/840687Fri, 30 Oct 2026 03:33:59 GMT<![CDATA[Reply to PySide6 UI looks different depending on which macOS built Python on Thu, 29 Oct 2026 20:33:52 GMT]]>@axu2 Hi,

Likely this blog article: https://www.qt.io/blog/qt-on-macos-26-tahoe

]]>https://forum.qt.io/post/840679https://forum.qt.io/post/840679Thu, 29 Oct 2026 20:33:52 GMT<![CDATA[Reply to PySide6 UI looks different depending on which macOS built Python on Wed, 28 Oct 2026 21:04:32 GMT]]>Yes, that worked, thank you!

where is the guide you mentioned?

]]>https://forum.qt.io/post/840643https://forum.qt.io/post/840643Wed, 28 Oct 2026 21:04:32 GMT<![CDATA[Reply to PySide6 UI looks different depending on which macOS built Python on Wed, 28 Oct 2026 20:46:42 GMT]]>Qt's macOS guidance describes adding this key to the app's Info.plist:

<key>UIDesignRequiresCompatibility</key>
<true/>
Please update Info.plist file and try again.

]]>https://forum.qt.io/post/840642https://forum.qt.io/post/840642Wed, 28 Oct 2026 20:46:42 GMT<![CDATA[Reply to PySide6 UI looks different depending on which macOS built Python on Wed, 28 Oct 2026 20:36:20 GMT]]>calling setStyle('Windows') looks terrible on macOS, but that's expected.

calling setStyle('Fusion') looks OK but not ideal.

calling setStyle('macOS') doesn't change anything.

I think the problem is related to the python version, not Qt. since the red/yellow/green button in top left get liquid glassified.

]]>https://forum.qt.io/post/840641https://forum.qt.io/post/840641Wed, 28 Oct 2026 20:36:20 GMT<![CDATA[Reply to PySide6 UI looks different depending on which macOS built Python on Wed, 28 Oct 2026 20:07:03 GMT]]>In my opinion, I suggest to use QStyleFactory class.
print(QStyleFactory.keys())
You can get available styles through call this function and, keep macos style.
Good luck to you.

]]>https://forum.qt.io/post/840640https://forum.qt.io/post/840640Wed, 28 Oct 2026 20:07:03 GMT