ubiquity crashed with ValueError in command(): I/O operation on closed file.

[Jean-Baptiste Lallement]

Test Case:
1. Launch ubiquity
2. Select a language and continue
3. Select a keyboard layout and quit

Actual result
This crash happens when Ubiquity exits.

ProblemType: Crash
DistroRelease: Ubuntu 18.04
Package: ubiquity 18.04.3
ProcVersionSignature: Ubuntu 4.15.0-10.11-generic 4.15.3
Uname: Linux 4.15.0-10-generic x86_64
ApportVersion: 2.20.8-0ubuntu10
Architecture: amd64
CasperVersion: 1.389
Date: Tue Mar 13 10:48:44 2018
ExecutablePath: /usr/lib/ubiquity/bin/ubiquity
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --- maybe-ubiquity
InterpreterPath: /usr/bin/python3.6
LiveMediaBuild: Ubuntu 18.04 LTS "Bionic Beaver" - Alpha amd64 (20180313)
ProcCmdline: /usr/bin/python3 /usr/lib/ubiquity/bin/ubiquity -d
ProcEnviron: Error: [Errno 13] Permission non accordée: '/proc/5714/environ'
Python3Details: /usr/bin/python3.6, Python 3.6.4+, python3-minimal, 3.6.4-1
PythonArgs: ['/usr/lib/ubiquity/bin/ubiquity', '-d']
PythonDetails: /usr/bin/python2.7, Python 2.7.14+, python-minimal, 2.7.14-4
SourcePackage: ubiquity
Title: ubiquity crashed with ValueError in command(): I/O operation on closed file.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Launchpad Janitor (janitor)]

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

[Willem Hobers (whobers)]

Was testing the daily ISO in a virtual machine. Ubiquity didn't adapt to the actual screen size; I couldn't click next. So I closed ubiquity and then this crash happened.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1755452

[Yousuf 'Jay' Philips (philipz85)]

Happened to me on xubuntu 20.04 daily iso from march 20th 2020.

[Brian Murray (brian-murray)]

I was able to recreate this on a 20.04 daily iso dated 20200330 by clicking quit after selecting a language. This happens both when choosing "Install Ubuntu" or launching "Install Ubuntu" from the desktop.

[Thomas Hill (t-hill)]

Able to recreate on Ubuntu Desktop amd64 20.10 daily 20200516

[Benjamin Drung (bdrung)]

Able to recreate on Ubuntu Desktop amd64 22.04 daily 2022-04-08.