Comment 46 for bug 1751252

I can confirm that the package version from bionic-proposed solves the problem.

During an installation I used Dell 2715Q with settings as in the screenshot attached (single monitor mode, 200% scaling).

# the updated package
apt policy ubiquity
ubiquity:
  Installed: 18.04.14.1
  Candidate: 18.04.14.1
  Version table:
 *** 18.04.14.1 500
        500 http://archive.ubuntu.com/ubuntu bionic-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     18.04.14 500
        500 http://archive.ubuntu.com/ubuntu bionic/main amd64 Packages

Before adding "deb http://archive.ubuntu.com/ubuntu/ bionic-proposed main restricted" to sources.list and doing `apt install ubiquity` I had this in syslog:

ay 13 12:39:12 ubuntu ubiquity: W: --force-yes is deprecated, use one of the options starting with --allow instead.
May 13 12:39:12 ubuntu ubiquity[4617]: debconffilter_done: ubi-usersetup (current: ubi-usersetup)
May 13 12:39:12 ubuntu ubiquity[4617]: Step_before = stepUserInfo
May 13 12:39:12 ubuntu kernel: [ 249.861407] do_trap: 40 callbacks suppressed
May 13 12:39:12 ubuntu kernel: [ 249.861410] traps: ubiquity[4617] trap int3 ip:7fc1a36cdc41 sp:7ffe6a90a760 error:0 in libglib-2.0.so.0.5600.1[7fc1a367c000+113000]
May 13 12:39:21 ubuntu update-notifier[4223]: GtkDialog mapped without a transient parent. This is discouraged.
May 13 12:39:22 ubuntu /install.py: Exception during installation:
May 13 12:39:22 ubuntu /install.py: Traceback (most recent call last):
May 13 12:39:22 ubuntu /install.py: File "/usr/share/ubiquity/install.py", line 765, in <module>
May 13 12:39:22 ubuntu /install.py: install.run()
May 13 12:39:22 ubuntu /install.py: File "/usr/share/ubiquity/install.py", line 135, in run
May 13 12:39:22 ubuntu /install.py: self.copy_all()
May 13 12:39:22 ubuntu /install.py: File "/usr/share/ubiquity/install.py", line 513, in copy_all
May 13 12:39:22 ubuntu /install.py: self.db.progress('SET', 10 + copy_progress)
May 13 12:39:22 ubuntu /install.py: File "/usr/lib/python3/dist-packages/debconf.py", line 83, in <lambda>
May 13 12:39:22 ubuntu /install.py: lambda *args, **kw: self.command(command, *args, **kw))
May 13 12:39:22 ubuntu /install.py: File "/usr/lib/python3/dist-packages/debconf.py", line 104, in command
May 13 12:39:22 ubuntu /install.py: status = int(status)
May 13 12:39:22 ubuntu /install.py: ValueError: invalid literal for int() with base 10: ''

After the update a newly started installation went just fine.