我的 Ubuntu 19.10 桌面左侧的收藏夹栏（Ubuntu Dock）不断消失。有时会持续几天，有时一天会出现几次。我在这里找到了参考资料：任务栏不断消失！和这里：Ubuntu 16.04 2018 年 1 月 3 日更新导致屏幕/访问问题对于以前的版本。
我在以前的版本上也遇到过这个问题，但是现在已经好转，并且又在最新和最好的版本中回归了。:(
摘自系统日志：
Jan 18 20:14:07 westeros geoclue[26909]: Service not used for 60 seconds. Shutting down..
Jan 18 20:14:07 westeros systemd[1]: geoclue.service: Main process exited, code=killed, status=15/TERM
Jan 18 20:14:07 westeros systemd[1]: geoclue.service: Succeeded.
Jan 18 20:14:29 westeros xdg-desktop-por[27953]: Failed to get application states: GDBus.Error:org.freedesktop.portal.Error.Failed: Could not get window list: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: App introspection not allowed
Jan 18 20:15:13 westeros pulseaudio[27668]: W: [pulseaudio] resampler.c: Support for resampler 'src-sinc-best-quality' not compiled in, reverting to 'auto'.
Jan 18 20:15:29 westeros xdg-desktop-por[27953]: Failed to get application states: GDBus.Error:org.freedesktop.portal.Error.Failed: Could not get window list: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: App introspection not allowed
Jan 18 20:15:57 westeros gnome-shell[28046]: Some code accessed the property 'discreteGpuAvailable' on the module 'appDisplay'. That property was defined with 'let' or 'const' inside the module. This was previously supported, but is not correct according to the ES6 standard. Any symbols to be exported from a module must be defined with 'var'. The property access will work as previously for the time being, but please fix your code anyway.
Jan 18 20:16:29 westeros xdg-desktop-por[27953]: Failed to get application states: GDBus.Error:org.freedesktop.portal.Error.Failed: Could not get window list: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: App introspection not allowed
Jan 18 20:17:01 westeros CRON[27097]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jan 18 20:17:29 westeros xdg-desktop-por[27953]: Failed to get application states: GDBus.Error:org.freedesktop.portal.Error.Failed: Could not get window list: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: App introspection not allowed
Jan 18 20:18:12 westeros PackageKit: daemon quit
Jan 18 20:18:12 westeros systemd[1]: packagekit.service: Main process exited, code=killed, status=15/TERM
Jan 18 20:18:12 westeros systemd[1]: packagekit.service: Succeeded.
Jan 18 20:18:29 westeros xdg-desktop-por[27953]: Failed to get application states: GDBus.Error:org.freedesktop.portal.Error.Failed: Could not get window list: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: App introspection not allowed
Jan 18 20:19:06 westeros gnome-shell[28046]: # _g_io_module_get_default: Found default implementation gvfs (GDaemonVfs) for ‘gio-vfs’
Jan 18 20:19:06 westeros dbus-daemon[27676]: [session uid=1000 pid=27676] Activating via systemd: service name='org.gnome.Terminal' unit='gnome-terminal-server.service' requested by ':1.388' (uid=1000 pid=27139 comm="/usr/bin/gnome-terminal.real --window " label="unconfined")
Jan 18 20:19:06 westeros systemd[27649]: Starting GNOME Terminal Server...
Jan 18 20:19:06 westeros dbus-daemon[27676]: [session uid=1000 pid=27676] Successfully activated service 'org.gnome.Terminal'
Jan 18 20:19:06 westeros systemd[27649]: Started GNOME Terminal Server.
Jan 18 20:19:06 westeros gnome-shell[28046]: # _g_io_module_get_default: Found default implementation dconf (DConfSettingsBackend) for ‘gsettings-backend’
Jan 18 20:19:06 westeros gnome-shell[28046]: # watch_fast: "/org/gnome/terminal/legacy/" (establishing: 0, active: 0)
Jan 18 20:19:06 westeros gnome-shell[28046]: # unwatch_fast: "/org/gnome/terminal/legacy/" (active: 0, establishing: 1)
Jan 18 20:19:06 westeros gnome-shell[28046]: # watch_established: "/org/gnome/terminal/legacy/" (establishing: 0)
Jan 18 20:19:29 westeros xdg-desktop-por[27953]: Failed to get application states: GDBus.Error:org.freedesktop.portal.Error.Failed: Could not get window list: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: App introspection not allowed
答案1
我按下alt- ，f2然后r在命令窗口中输入以重新启动 GNOME Shell，收藏夹栏就会返回。
需要有比这更好的解决方案。