[GTALUG] Kernel and/or X upgrade broke my video setup

[Scott Sullivan]

On October 11, 2017 10:19:28 AM EDT, ac via talk <talk at gtalug.org> wrote:
>On Wed, 11 Oct 2017 10:01:07 -0400
>Scott Sullivan via talk <talk at gtalug.org> wrote:.
>> Desktop implement UIs that talk to this functionality, and handle the
>
>> 'memory' of layouts. KDE's for example will remember transient
>> moinitor configureations, like my two different laptop docks at home
>> and work, and will restore the right layout for each, matching
>> against the Vendor IDs of the monitors.
>> 
>Okay, but after a kernel update / distro update - no configs 'should
>have' been over written... 
>
>as it seems there has been config changes (both screens are still
>working & mouse moves to both screens, etc etc)
>
Not necessarily. Software is free to mangle your configs at run time. Distro will knowingly or unknowingly push updates from the upstream that 'upgrade' preferences files in ways that don't roll back. Especially in desktop applications.

Firefox will be doing this with the 57 release as we learned last night.

But another factor is driver updates can also result in the Output names changing. I've seen this in my own laptop. Usually as the generic drives gets tweaked to be aware of the specific model.

In that case the old config doesn't match the remembered state and would reasonable fall back to defaults. And defaults are the convention of the person that wrote the software.
-- 
Scott Sullivan