Comment 8 for bug 1749289

xnox: sadly there was a misunderstanding - I didn't take any actions about it since the merge request was marked "on hold", but I hit some issues with the installer after removing fcntl.ioctl(0, termios.TIOCSCTTY, 1)
The terminal debconf tools were failing without it.

I came up with 2 other ways of mitigating this issue:
https://code.launchpad.net/~dgadomski/ubiquity/+git/ubiquity/+ref/lp1749289-a - preventing cancelling the first page of the installer

https://code.launchpad.net/~dgadomski/ubiquity/+git/ubiquity/+ref/lp1749289-b - implement do_reboot method in the debconf_ui wizard to prevent AttributeError caused by calling missing method.

Please consider using any of those instead (both branches include reverting the previous change).