sylpheed cuts off text of recipents with a long enough list of recipents

To reproduce receive and email with lots of recipients like the one I have a screenshot attached sent to many mailing lists. Then click on the message and in the summary of to and from above the bottom of the message try and read the list of to adresses and it does not wrap to the next line it gets cut off.

lsb sylpheed:
  Installed: 3.5.1-1ubuntu2
  Candidate: 3.5.1-1ubuntu2
  Version table:
 *** 3.5.1-1ubuntu2 500
        500 http://us.archive.ubuntu.com/ubuntu zesty/universe amd64 Packages
        100 /var/lib/dpkg/status
Description: Ubuntu Zesty Zapus (development branch)
Release: 17.04

I expected the list of addresses to wrap so I could read them all in the summary line instead of beging cut off the end of the window.

ProblemType: Bug
DistroRelease: Ubuntu 17.04
Package: sylpheed 3.5.1-1ubuntu2
ProcVersionSignature: Ubuntu 4.9.0-12.13-generic 4.9.2
Uname: Linux 4.9.0-12-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.4-0ubuntu2
Architecture: amd64
CurrentDesktop: LXDE
Date: Wed Feb 15 15:38:40 2017
InstallationDate: Installed on 2017-01-27 (19 days ago)
InstallationMedia: Lubuntu 17.04 "Zesty Zapus" - Alpha amd64 (20170125)
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: sylpheed
UpgradeStatus: No upgrade log present (probably fresh install)