KDE file dialog column resize no longer possible?

[René J. V. Bertin]

Hmmm, I never see a scrollbar.

Maybe the easiest workaround would be a mode where the user can disable all 
automatic sizing (possibly after getting a good initial setting), and then use 
the user's size choices? That's the behaviour you get on Mac (and MSWin) and 
something I more or less expect everywhere. I often deal with files that have 
long names for which I don't want the required width to be allocated - and iin 
general I strongly believe that the user should at least feel in control of his 
GUI (there's a reason I don't use Gnome ;))
Dialog information is already saved so there should be no need to implement 
something new for that.

I'm currently a bit handicapped by the recent requirement bump to Qt 5.10 (which 
is not supported on my main machine and I thus don't have on my Linux rig 
either). I'm slowly working my way around that but kio still a little way off.