I found this workaround:
https://www.virtualbox.org/ticket/12738
~$ export LIBGL_ALWAYS_SOFTWARE=1 ~$ webbrowser-app
now i can start webbrowser-app on Ubuntu 15.10 Alpha at Virtualbox 5.0
I found this workaround:
https:/ /www.virtualbox .org/ticket/ 12738
~$ export LIBGL_ALWAYS_ SOFTWARE= 1
~$ webbrowser-app
now i can start webbrowser-app on Ubuntu 15.10 Alpha at Virtualbox 5.0