Brightness up/down keys stopped working?

[David Rosenstrauch]

On 06/20/2017 11:46 AM, David Rosenstrauch wrote:
> I'm not sure what triggered this, but it looks like some recent upgrade 
> has disabled the XF86MonBrightnessUp & Down keys, and I think the issue 
> might be limited to XFCE.  (When I run xev under XFCE, it never 
> registers that key press.  But when I launch fluxbox in VT8 and run xev 
> there it does.)
> 
> Anyone aware of any recent release that might have caused this?  (And, 
> if so, how I might fix it?)
> 
> Thanks,
> 
> DR


A little more info:

Although xev doesn't register the brightness key events, it does seem to 
be firing some brightness related events that are unexpected:

RRNotify event, serial 68, synthetic NO, window 0x3e00001,
     subtype XRROutputPropertyChangeNotifyEvent
     output eDP1, property Backlight, timestamp 243122, state NewValue

DR