Input of disk security key not possible inside VirtualBox

[Karl-Philipp Richter]

Installations of Ubuntu 18.10 and 19.04-daily are not possible with an encrypted disk setup because the input field for the security key never shows a cursor after clicking on the field. Tab navigation seems to have no effect and cannot be used to reach the input field (or any other control on the wizard page). Going back and forward again has no effect.

The used VirtualBox version is 5.2.20 on an Ubuntu 18.10 host.

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: ubiquity 19.04.2 [modified: lib/partman/automatically_partition/question]
ProcVersionSignature: Ubuntu 4.18.0-10.11-generic 4.18.12
Uname: Linux 4.18.0-10-generic x86_64
ApportVersion: 2.20.10-0ubuntu14
Architecture: amd64
CasperVersion: 1.399
Date: Sun Nov 18 12:43:44 2018
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd quiet splash --- maybe-ubiquity
LiveMediaBuild: Ubuntu 19.04 "Disco Dingo" - Alpha amd64 (20181113)
ProcEnviron:
 TERM=linux
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=C.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)