Firefox Sync verification prompt and preferences lock background windows

[Jeb E.]

The GNOME Web/Epiphany Web Browser 'Preferences' screen locks onto the foreground, forbidding any action in the background web browser windows.
This is not generally an issue until/unless the user wants to set up the Firefox Sync service, located within Preferences, which in turn requires a verification link sent via email to be opened up within the browser. If the user does not have another browser installed and/or an email client with built-in browser set up, the user is forced into downloading, installing, and using another browser temporarily to sign in.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: epiphany (not installed)
ProcVersionSignature: Ubuntu 4.15.0-20.21-lowlatency 4.15.17
Uname: Linux 4.15.0-20-lowlatency x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Fri May 4 11:39:46 2018
InstallationDate: Installed on 2018-05-01 (3 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: epiphany
UpgradeStatus: No upgrade log present (probably fresh install)

[Jeb E. (jebeld17)]

Bug report info added for the 'epiphany' package into the Gnome Bugzilla bugtracker. See "Affects" list at the top of the original Launchpad bug (https://bugs.launchpad.net/epiphany/+bug/1769192) or visit https://bugzilla.gnome.org/show_bug.cgi?id=795807.

All the help is needed! :)