我是 kubuntu 的新手，并且在过去的几个月中一直在使用它，没有出现任何（非自身原因造成的）问题...
操作系统是 Ubuntu Linux 17.04，内核是 x86_64 上的 Linux 4.10.0-38-generic
昨天晚上我下班后，笔记本电脑还在运行；今天早上我发现 plasmashell 崩溃了——我看到屏幕变黑了，但鼠标、其他程序、多个桌面、dolphin 等都运行正常。只是没有“菜单”栏，没有桌面壁纸。重新启动、登录、看到壁纸，然后它又崩溃了。
从 konsole 运行 plasmashell；壁纸短暂显示（如启动时一样），然后消失。以下是输出
kpizzolatto@SES-L02:~$ plasmashell
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
Reusing existing ksycoca
Recreating ksycoca file ("/home/kpizzolatto/.cache/ksycoca5_en_mje4N4X9OuhHvbu8uq3wZl4cjRo=", version 303)
Still in the time dict (i.e. deleted files) ("apps")
kf5.kservice.sycoca: Parse error in "/home/kpizzolatto/.config/menus/applications-merged/xdg-desktop-menu-dummy.menu" , line 1 , col 1 : "unexpected end of file"
Menu "applications-kmenuedit.menu" not found.
Saving
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
No file found for ".xml" , even though update-mime-info said it would exist.
Either it was just removed, or the directory doesn't have executable permission... ("/home/kpizzolatto/.local/share/mime", "/usr/share/mime")
No file found for ".xml" , even though update-mime-info said it would exist.
Either it was just removed, or the directory doesn't have executable permission... ("/home/kpizzolatto/.local/share/mime", "/usr/share/mime")
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/1680x1050 package/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/1680x1050 package/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/1680x1050 package/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/1680x1050 package/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/1680x1050 package/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/1680x1050 package/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/regular/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/regular/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/regular/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/Random Stuff/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/Random Stuff/"
No metadata file in the package, expected it at: "/home/kpizzolatto/SES/kjp/Wallpaper/Roger Dean/Random Stuff/"
Connecting to deprecated signal QDBusConnectionInterface::serviceOwnerChanged(QString,QString,QString)
Trying to use rootObject before initialization is completed, whilst using setInitializationDelayed. Forcing completion
file:///usr/share/plasma/plasmoids/org.kde.plasma.digitalclock/contents/ui/main.qml:78:27: Unable to assign [undefined] to QStringList
file:///usr/share/plasma/plasmoids/org.kde.plasma.digitalclock/contents/ui/main.qml:37: TypeError: Cannot read property 'DateTime' of undefined
Both point size and pixel size set. Using pixel size.
Both point size and pixel size set. Using pixel size.
Both point size and pixel size set. Using pixel size.
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
Trying to use rootObject before initialization is completed, whilst using setInitializationDelayed. Forcing completion
file:///usr/lib/x86_64-linux-gnu/qt5/qml/QtQuick/Controls/Button.qml:99: TypeError: Cannot read property of null
Notifications service registered
libkcups: Create-Printer-Subscriptions last error: 0 successful-ok
libkcups: Get-Jobs last error: 0 successful-ok
libkcups: Get-Jobs last error: 0 successful-ok
Plasma Shell startup completed
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/kpizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
libkcups: 2
KCrash: Attempting to start /usr/bin/plasmashell from kdeinit
sock_file=/run/user/1000/kdeinit5__0
KCrash: crashing... crashRecursionCounter = 2
KCrash: Application Name = plasmashell path = /usr/bin pid = 10767
KCrash: Arguments: /usr/bin/plasmashell
KCrash: Attempting to start /usr/lib/x86_64-linux-gnu/libexec/drkonqi from kdeinit
sock_file=/run/user/1000/kdeinit5__0
QSocketNotifier: Invalid socket 8 and type 'Read', disabling...
QSocketNotifier: Invalid socket 21 and type 'Read', disabling...
QSocketNotifier: Invalid socket 9 and type 'Read', disabling...
[1]+ Stopped plasmashell
kpizzolatto@SES-L02:~$ Unable to start Dr. Konqi
Re-raising signal for core dump handling.
[1]+ Segmentation fault (core dumped) plasmashell
我看到其他一些人尝试以 root 身份运行 kdeshell，创建一个全新的用户，因此尝试...新用户，登录 - 几乎相同的行为，但输出略有不同（我猜是因为没有个性化）
sespizzolatto@SES-L02:~$ plasmashell
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
Connecting to deprecated signal QDBusConnectionInterface::serviceOwnerChanged(QString,QString,QString)
Trying to use rootObject before initialization is completed, whilst using setInitializationDelayed. Forcing completion
Both point size and pixel size set. Using pixel size.
Both point size and pixel size set. Using pixel size.
Both point size and pixel size set. Using pixel size.
log_klipper: Failed to load history resource. Clipboard history cannot be read. : History file does not exist
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
kf5.kcoreaddons.desktopparser: Could not locate service type file kservicetypes5/plasma-popupapplet.desktop, tried ("/home/sespizzolatto/.local/share", "/usr/share/usr/share/xsessions/plasma", "/usr/local/share", "/usr/share", "/var/lib/snapd/desktop")
Trying to use rootObject before initialization is completed, whilst using setInitializationDelayed. Forcing completion
file:///usr/lib/x86_64-linux-gnu/qt5/qml/QtQuick/Controls/Button.qml:99: TypeError: Cannot read property of null
Notifications service registered
libkcups: Create-Printer-Subscriptions last error: 0 successful-ok
libkcups: Get-Jobs last error: 0 successful-ok
libkcups: Get-Jobs last error: 0 successful-ok
Plasma Shell startup completed
libkcups: 2
KCrash: Attempting to start /usr/bin/plasmashell from kdeinit
sock_file=/run/user/1001/kdeinit5__0
KCrash: crashing... crashRecursionCounter = 2
KCrash: Application Name = plasmashell path = /usr/bin pid = 8436
KCrash: Arguments: /usr/bin/plasmashell
KCrash: Attempting to start /usr/lib/x86_64-linux-gnu/libexec/drkonqi from kdeinit
sock_file=/run/user/1001/kdeinit5__0
QSocketNotifier: Invalid socket 8 and type 'Read', disabling...
QSocketNotifier: Invalid socket 19 and type 'Read', disabling...
QSocketNotifier: Invalid socket 9 and type 'Read', disabling...
[1]+ Stopped plasmashell
sespizzolatto@SES-L02:~$ Unable to start Dr. Konqi
Re-raising signal for core dump handling.
[1]+ Segmentation fault (core dumped) plasmashell
sespizzolatto@SES-L02:~$
最后，我还看到一些人尝试以 root 身份成功，但这也没有什么区别——壁纸出现了一会儿，然后消失，没有菜单，没有“托盘”等等。
答案1
解决方法，而不是修复。禁用系统托盘中的打印机图标参考https://superuser.com/a/1221053
但还是不明白它为何停止工作。