ubiquity fails to start under wayland

[Jean-Baptiste Lallement]

artful desktop 20170707.1

Ubiquity fails to start from the live session.

From syslog
Jul 7 12:27:51 ubuntu ubiquity[4375]: Ubiquity 17.04.9
Jul 7 12:27:51 ubuntu ubiquity[4375]: Exception in GTK frontend (invoking crash handler):
Jul 7 12:27:51 ubuntu ubiquity[4375]: Traceback (most recent call last):
Jul 7 12:27:51 ubuntu ubiquity[4375]: File "/usr/lib/ubiquity/bin/ubiquity", line 655, in <module>
Jul 7 12:27:51 ubuntu ubiquity[4375]: main(oem_config)
Jul 7 12:27:51 ubuntu ubiquity[4375]: File "/usr/lib/ubiquity/bin/ubiquity", line 641, in main
Jul 7 12:27:51 ubuntu ubiquity[4375]: install(query=options.query)
Jul 7 12:27:51 ubuntu ubiquity[4375]: File "/usr/lib/ubiquity/bin/ubiquity", line 270, in install
Jul 7 12:27:51 ubuntu ubiquity[4375]: wizard = ui.Wizard(distro)
Jul 7 12:27:51 ubuntu ubiquity[4375]: File "/usr/lib/ubiquity/ubiquity/frontend/gtk_ui.py", line 239, in __init__
Jul 7 12:27:51 ubuntu ubiquity[4375]: self.watch = Gdk.Cursor.new(Gdk.CursorType.WATCH)
Jul 7 12:27:51 ubuntu ubiquity[4375]: TypeError: constructor returned NULL
Jul 7 12:27:51 ubuntu ubiquity[4375]:
Jul 7 12:27:52 ubuntu ubiquity[4375]: log-output -t ubiquity /usr/share/apport/apport-gtk
Jul 7 12:27:57 ubuntu kernel: [ 774.404538] update-notifier[4425]: segfault at 0 ip (null) sp 00007ffd666ed328 error 14 in update-notifier[5580e6078000+e000]

[Sebastien Bacher (seb128)]

Didier uploaded a casper change to default to an xorg session which should workaround that bug for now, still ubiquity should work under wayland

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Jeremy Bícha (jbicha)]

This isn't going to happen for Ubuntu 17.10.

As a workaround, we're forcing the X session by default in the live environment on the ISO.