Ubuntu MATE installer crashes when one attempts to change timezones using the clickable map

[Aaron Rainbolt]

Hardware: HP Elitebook 8570p, UEFI, no secure boot, Broadcom WiFi, 16 GB RAM, 120 GB SSD, 3rd Gen Intel Core i5.

Steps to reproduce:

1. Boot the latest daily ISO of Ubuntu MATE Lunar.
2. Choose to "Try or Install Ubuntu MATE" on the GRUB menu.
3. Click "Install Ubuntu MATE".
4. Proceed with the rest of the installer, accepting all of the default options until you reach the "Where are you?" screen.
5. Click on the timezone map to attempt to change your timezone to Central Daylight Time (try clicking in the Chicago area).

Expected result: The city you clicked closest to should be selected, changing your timezone if appropriate.

Actual result: Ubiquity crashes.

ProblemType: Bug
DistroRelease: Ubuntu 23.04
Package: ubiquity 23.04.4
ProcVersionSignature: Ubuntu 6.1.0-16.16-generic 6.1.6
Uname: Linux 6.1.0-16-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.26.0-0ubuntu2
Architecture: amd64
CasperMD5CheckResult: pass
CasperVersion: 1.480
CurrentDesktop: MATE
Date: Sun Mar 19 02:04:21 2023
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntu-mate.seed maybe-ubiquity quiet splash ---
LiveMediaBuild: Ubuntu-MATE 23.04 "Lunar Lobster" - Alpha amd64 (20230318)
ProcEnviron:
 LANG=C.UTF-8
 PATH=(custom, no user)
 SHELL=/bin/bash
 TERM=xterm-256color
 XDG_RUNTIME_DIR=<set>
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)