GUI Issues: Active window on top, scroolbar without scrooling buttons

[Robert Mittendorf]

Hello fellow Qubes users,

today I have a few questions about the GUI handling in Qubes. I use
Qubes 3.2 with Xfce desktop dom0.

1) If a window that already exists is set to active, it is not shown on
top. Example: I open up a programm that is alrady running and that
starts only a single instance (per Qube/VM) - is there a fix?

2) The scroolingbar of Thunderbird is a little weird. There are no
scrooling buttons (up/down) and when I click somewhere in the range of
the scroolbar the windows content will directly jump to that very
position, instead of just moving one screen towards that direction.
I created the
~/.config/gtk-3.0/gtk.css as follows:

.scrollbar {
-GtkScrollbar-has-backward-stepper: true;
-GtkScrollbar-has-forward-stepper: true;
}

Now the terminal has scroolbar buttons, but Thunderbird still doesnt.
Even if I use a new thunderbird profile......

I have tried solving the second issue for about 3 hours now.....