[tor-talk] tor browser graphics only updating when move mouse over window

[aingetep at tutanota.de]

Hello,

My TOR browser exhibits the following symptom. The graphics on its window  don't update unless I move the mouse pointer over it. 

Is this happening to anyone else?

Tor browser is 6.0.2, based on Mozilla 45.2.0, running on a Debian unstable.

#uname -srvm
Linux 4.6.0-1-amd64 #1 SMP Debian 4.6.3-1 (2016-07-04) x86_64

Thanks in advance.