FreeBSD 11.2. I upgrade kde4 to kde5.

1. systemsettings5: If choice "Desktop Theme" get clean right side whithout options and error if loaded systemsettings5 from konsole: "
org.kde.kcoreaddons: Error loading plugin "kcm_desktoptheme" "The shared library was not found."
Plugin search paths are ("/usr/local/lib/plugins", "/usr/local/lib/qt5/plugins", "/usr/local/bin")
The environment variable QT_PLUGIN_PATH might be not correctly set
"file:///usr/local/share/kpackage/kcms/kcm_desktoptheme/contents/ui/main.qml"
"Error loading QML file.\n227: Type FileDialog unavailable\n47: plugin cannot be loaded for module \"Qt.labs.folderlistmodel\": Module loaded for URI '' does not implement QQmlTypesExtensionInterface\n""
https://forums.freebsd.org/attachments/1552917367852-png.6255/

2. Not have transparent effect in konsole.

I install clean FreeBSD 11.2 and KDE5 to VirtualBox: Not have this two problem.
https://forums.freebsd.org/attachments/screenshot_20190320_010936-png.6268/

# pkg info kde5
kde5-5.12.5.18.08.1
Name : kde5
Version : 5.12.5.18.08.1
Installed on : Mon Mar 4 21:27:30 2019 +07
Origin : x11/kde5
Architecture : FreeBSD:11:*
Prefix : /usr/local
Categories : x11 kde
Licenses : LGPL20
Maintainer : kde@FreeBSD.org
WWW : https://www.kde.org
Comment : KDE Plasma Desktop and Applications (current)
Options :
KDEADMIN : on
KDEEDU : on
KDEGAMES : on
KDEGRAPHICS : on
KDEMULTIMEDIA : on
KDENETWORK : on
KDEPIM : on
KDEUTILS : on
PULSEAUDIO : off
Annotations :
repo_type : binary
repository : FreeBSD-quarterly
Flat size : 25.1KiB
Description :
KDE is a powerful Free Software graphical desktop environment for Linux
and Unix workstations.

This package does not contain anything by itself -- it is a
"meta-port" that depends on other KDE packages. Its sole purpose is
to require dependencies so users can install this package only and
have all the KDE stuff pulled in by the port/package dependency mechanism.

x11/kde5 contains current KDE Frameworks, Plasma Desktop and Applications.

I now my place Antarctida (station Vostok) Internet access only 256kbit full upgrade impossible.
I have only local repository. Access for external repo very slow.
M.b. I get solution for fixed this problem. Thanks.

1. reinstall all kde5, before delete all libs kde4 and qt4 - "Desktop Themes" work normal.

2. I upgrade ports to last update for 26 april 2019.

- make and reinstall mesa-libs to mesa-18.3.2 and konsole (18.01.1) now have transparent effect. Compiled without 'wayland' - now this not work for my FreeBSD 11.2
.
- another soft not upgrade - upgrade only mesa-libs.

but after upgrade mesa-dri, drm-fbsd11.2-kmod, konsole-19.04.0...
x11-drivers/xf86-video-intel not different and not upgrade.

-!!! if disable "Blur" effects in KDE5 Settings "Desktop effects" - in "Desktop Themes" return transparent effect for interface too!

-!!! if enable "Blur" in konsole Settings - transparent for konsole not have!

Blur effect in mesa - is broken
... but "blur" not need for me. Blur is off