Document installation of qt5-style-plugins

[Teresa e Junior]

xubuntu-default-settings has both the file /etc/skel/.config/Trolltech.conf, which sets the look of Qt applications, and /etc/X11/Xsession.d/56xubuntu-session, which sets QT_QPA_PLATFORMTHEME=gtk2.

The package qt5-style-plugins is still needed, though, for Qt 5 applications to use the Greybird theme and Xfce4 font settings.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: xubuntu-default-settings 17.10.0
ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4
Uname: Linux 4.13.0-16-generic x86_64
ApportVersion: 2.20.7-0ubuntu3.1
Architecture: amd64
CurrentDesktop: XFCE
Date: Sat Oct 28 12:16:00 2017
InstallationDate: Installed on 2017-04-23 (188 days ago)
InstallationMedia: Xubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
PackageArchitecture: all
SourcePackage: xubuntu-default-settings
UpgradeStatus: Upgraded to artful on 2017-10-28 (0 days ago)

[Theo Linkspfeifer (lastonestanding)]

Should "qt5-style-plugins" and its various dependencies be pulled in by default (as recommended package)? At least that is what Ubuntu MATE does.

---

$ sudo apt install --no-install-recommends qt5-style-plugins
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  libdouble-conversion1 libqt5core5a libqt5dbus5 libqt5gui5 libqt5network5
  libqt5widgets5 libxcb-icccm4 libxcb-image0 libxcb-keysyms1 libxcb-randr0
  libxcb-render-util0 libxcb-xinerama0 libxcb-xkb1 libxkbcommon-x11-0
Suggested packages:
  qt5-image-formats-plugins qtwayland5
Recommended packages:
  qttranslations5-l10n libqt5svg5 qt5-gtk-platformtheme
The following NEW packages will be installed:
  libdouble-conversion1 libqt5core5a libqt5dbus5 libqt5gui5 libqt5network5
  libqt5widgets5 libxcb-icccm4 libxcb-image0 libxcb-keysyms1 libxcb-randr0
  libxcb-render-util0 libxcb-xinerama0 libxcb-xkb1 libxkbcommon-x11-0
  qt5-style-plugins
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[Teresa e Junior (teresaejunior)]

I find it gives a good first impression when people install Qt applications and they look similar to the desktop. Don't know if there is room for it in the ISO, though.

[Theo Linkspfeifer (lastonestanding)]

It is mentioned in the release notes for 17.04 that an extra installation of qt5-style-plugins is needed, but that may be not easy to find.

https://wiki.xubuntu.org/releases/17.04/release-notes

We will have to wait for an answer from the Xubuntu team.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Sean Davis (bluesabre)]

We don't want to include it on the ISO because it pulls quite a few other QT dependencies. However, we should better surface this issue on the documentation.

Since Xubuntu now includes AptURL, we can even include a one-click installer.