Right, its the base dom0 memory settings, which you can also add
temporarily from grub menu (hit 'e', make change then boot). My dom0
'memory boost' in Qubes Global Settings is only 160MB.
The dom0 kernel I'm using is 4.19.43.
> I also have intel integrated graphics, maybe kabylake generation
Mine is Ivy Bridge, much older.
> at minimal qube memory 1564 and dom0 memory boost 5138 I am
> still finding it unusable the app menus don't appear , I keep
> fighting the taskbar widgets which then somehow I make appear on the
> desktop not the taskbar, then can't get them back on the taskbar,
> etc, which maybe a / the KDE learning curve ..... nice to see something
> less austere using Qubes, that I might be able to understand but
> if it requires me to change something in Grub and not just the Global
> Settings ...maybe time to give up :)
What happens if you change to sddm, what I'm using? In fact, it seems I
removed lightdm from dom0.
Also, for something easy to try, you can turn off the compositor with
Alt-Shift-F12. And the KDE compositor settings are under Display /
If none of that works, it may simply be a compatibility problem that the
old Fedora 25 possesses.