I was triggered by that comment as I had the same issue, but was unsure whether a bug report was correct, as I found the solution — in short, Qt6 QSensors implicitly depends on iio-sensor-proxy.Manually installing that and restarting Plasma / rebooting, the new feature works like a charm!
However, that package is neither pulled in by Qt nor by Plasma.
Effectively, users who do not install it manually are left without functional Ambient Light Sensor even though Plasma now supports this.
Would this be worth a bug report? If so, what would be the bug?
Improve Plasma to notify the user that the package needs to be installed for sensor support.
Change Plasma packaging so it pulls in that package.
Change Qt packaging so it pulls in that package.
Opening this here as I am unsure what is the correct bug and even the correct bugtracker .
Since you got it working by manually installing the package, this shows it’s not a bug in Plasma itself. The issue is that the distro doesn’t package iio-sensor-proxy as a dependency, so the proper place to report this is to the distro, since they’re responsible for packaging and managing dependencies, not Plasma.
As ArchLinux mentions iio-sensor-proxy as an optional dependency of qt6-sensors, it’s arguably not a packaging bug, but kind of left to the user to install this optional dependency if the feature is wanted.
To make it more visible to Arch users, I have added a small Tips & Tricks section to the Arch Wiki. As I am not yet allowed to insert links here: You can find it on the “KDE” page of the Arch Wiki by searching for “Ambient Light Sensor”.
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