MX Linux Forum

There may be a bug for adjusting brightness with the Fn - brightness keys. The dim-to-bright popup displays, but the bar adjusting brightness cannot be moved. It is stuck right in the middle at about 50 percent.

This is happening on both a Lenovo x220 (i7-model) and a a Lenovo x230 (with IPS display). The brightness buttons with MX19 works fine on Lenovo x201 and Lenovo T430s.

This may be a bug from Debian 10 because the LXDE live version of Debian also does not adjust brightness. However, I tested the two errant laptops with live USB versions of Kubuntu, Xubuntu, Sparky Linux minimal (openbox), and Mint Mate. The brightness could be adjusted fine on those live usb tests.

The x220 and x230 are two of the most common laptops to run linux on. I can try to solve this myself, but it's out of my area of expertise and would take awhile. Is there an easy solution, maybe applied in a coming MX update?

I wonder if any 5.x kernel makes a difference, simply from Popular Apps tab from MX Package Installer.

I updated the kernal to the most recent 5.x version in the MX repostory. It did not solve the backlight adjustment problem.

But I did stumble across a work-around using the excellent MX Tweaks.

MX Tweaks > Display tab > then set the brightness where you wish. The setting holds between reboots.

I set it to 99 brightness, and then use the "iris" color and brightness software to set color temperature and brightness. I've used it for years and the command line version for linux is only 30k and excellent.

https://iristech.co/iris-micro/

One question. I now have the newer kernal on the MX live USB which I use a lot. I could easily revert to the original older 4.x kernal version. Is there any risk in just keeping the newer 5.x kernal ?

No, if it causes no problems you may go on using / remove .. up to you ..

If you feel it's solved, you can (and please) click any check-mark icon on any post you like, to mark the thread :)

Thanks !!