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Chapter 57. Desktop

Cannot install downloaded RPM files from Nautilus

The yum backend to PackageKit does not support getting details about local files. As a consequence, when an RPM file is double clicked in the Nautilus file manger, the file is not installed, and the following error message is returned:
Sorry, this did not work, File is not supported
To work around this problem, either install the gnome-packagekit package to handle the double-click action, or manually install the files using the yum utility. (BZ#1434477)

Caps Lock LED status

When using an UTF-8 keymap, even though the caps lock function works properly, the caps lock LED is not updated while in TTY mode. For the LED to be correctly updated, starting from Red Hat Enterprise Linux 7.5, the administrator needs to create the /etc/udev/rules.d/99-kbd.rules configuration file as follows:
ACTION=="add", SUBSYSTEM=="leds",
ENV{DEVPATH}=="*/input*::capslock",
ATTR{trigger}="kbd-ctrlllock"
To reload the new udev rule, run these commands:
# udevadm control --reload-rules
# udevadm trigger
After this change, when pressing the caps lock key, caps lock LED changes its status as expected. (BZ#1470932, BZ#1256895)

Inconsistent GNOME Shell versions

The GNOME desktop environment currently displays different versions of GNOME Shell. For example, the version returned by the gnome-shell --version command is different from the version found in the Details section of Settings. (BZ#1511454)

Uninstall the 32-bit version of flatpak

Users are advised to uninstall the 32-bit version of the flatpak packages before updating to Red Hat Enterprise Linux 7.5 to prevent possible multilib conflicts. (BZ#1512940)

GNOME downgrade does not work

With the new version of GNOME (3.22) introduced in Red Hat Enterprise Linux 7.4, downgrading GNOME from version 3.22 to 3.14 using the yum downgrade or dnf downgrade commands is no longer possible. The only workaround lies in replacing the GNOME-related packages with their old versions. If you decide to downgrade manually, read the GNOME 3.16-3.22 release notes to find which functionalities you are losing. (BZ#1451876)

Wayland ignores keyboard grabs issued by X11 applications, such as virtual machines viewers

Currently, when running through the XWayland server, graphical clients that rely on the X11 software, such as remote desktop viewers or virtual machine managers, are unable to obtain the system keyboard shortcuts for their own use. As a consequence, activating these shortcuts in a guest window, such as a virt-manager guest display, affects the local desktop instead of the guest.
To work around the problem, use a Wayland native client with support for Wayland shortcuts inhibitor protocol, or switch back to the default GNOME session on X11 to run the X11 clients that require system keyboard shortcuts.
Note that Wayland is available as a Technology Preview. (BZ#1500397)

Superuser should not run graphical sessions

Opening a graphical session for the root user causes various bugs. The reason is that a graphical session is not meant to be used by superuser as it can cause serious and unexpected issues, is non-secure, and is against Unix principles. (BZ#1539772)

Keyboard not working in VM browsed by remote-viewer and virt-viewer

When run inside a Wayland session, remote-viewer and virt-viewer utilities do not recognize key events in a virtual machine. Moreover, Xwayland reports the following error:
send_key: assertion 'scancode != 0'
(BZ#1540056)

gnome-system-log does not work on Wayland

Currently, when logged in a Wayland session, the root user is not allowed to access the user's Xwayland display. As a consequence, running the gnome-system-log utility in terminal does not display system log files.
To work around this problem, run the following xhost server access control program as follows:
$ xhost +si:localuser:root
(BZ#1537529)

GUI screen is shown incorrectly

The X driver for Emulex Pilot2 and Pilot3 cards contains a bug when running at depth of color 16. This bug makes the graphics display unusable at this depth.
To make the display usable in some configurations, use 24 bpp image format. Alternatively, disable the shadow framebuffer abstraction layer in the xorg.conf file by using the ShadowFB off option. Note that disabling the shadow frambuffer may have significant performance impact. (BZ#1499129)

xrandr fails to provide some video modes

Different video drivers for X11 have different heuristics for adding display resolutions. In particular, the Intel and generic modesetting drivers provide different sets of video modes for some laptop displays. Consequently, some non-native video modes may not be available in all configurations.
To work around this problem, use a different video driver, or add resolutions to the output manually using the xrandr(1) command-line utility. (BZ#1478625)

radeon fails to reset hardware correctly

The radeon kernel driver currently does not reset hardware in the kexec context correctly. Instead, radeon falls over, which causes the rest of the kdump service to fail.
To work around this bug, blacklist radeon in kdump by adding the following line to the /etc/kdump.conf file:
dracut_args --omit-drivers "radeon"
force_rebuild 1
Restart the machine and kdump. After starting kdump, the force_rebuild 1 line may be removed from the configuration file.
Note that in this scenario, no graphics will be available during kdump, but kdump will complete successfully. (BZ#1509444)

nouveau fails to load Nvidia secboot firmware

In some Dell Coffeelake systems, the nouveau kernel module fails to load Nvidia secboot firmware for the pascal cards. As a consequence, Nvidia GPU on these systems occasionally does not work, and some of the Display ports on the system thus do not work as well.
If this bug causes trouble booting, blacklist nouveau to mitigate the problem. Note that this, however, will not make non-functional ports on the machine work correctly. (BZ#1535168)

Xchat status icon disappears from Top Icons panel

The Xchat status icon indicating incoming personal messages disappears from top icons panel after suspending the system and resuming it again.
Top icons installed using Gnome Software preserve the suspend mode and do not disappear from the panel. (BZ#1544840)

GDM does not activate hotplugged monitors

When a machine is booted without a monitor connected, the GNOME Display Manager (GDM) screen remains deactivated when a monitor is plugged in.
As a workaround, kill GDM while the monitor is plugged in by running:
# systemctl restart gdm.service
Alternatively, use the xrandr utility to activate the monitor. (BZ#1497303)

Wacom Expresskeys Remote not detected as tablet

The gnome-shell and control-center utilities do not detect unpaired Wacom Expresskeys Remote devices (EKRs). As a consequence, within the Wacom settings, there is no way to map the buttons on the EKR.
Currently, EKR works only when it is paired to a tablet with a built-in pad. (BZ#1543631)

Synaptics dependency removes xorg-x11-drivers

Later releases of Red Hat Enterprise Linux 7 contain the xorg-x11-drv-libinput driver for X, which can potentially provide a superior experience for some input devices. Users attempting to switch to xorg-x11-drv-libinput can try removing the xorg-x11-drv-synaptics driver, which is required by the xorg-x11-drivers package. However, removing synaptics requires removing xorg-x11-drivers.
To work around this issue, remove xorg-x11-drivers. This package exists only to install a reasonable collection of drivers at system setup time, and removing it has no runtime impact. Any X driver already installed will be updated as expected. (BZ#1516970)

T470s docking station jack does not work on resume

After suspending and resuming ThinkPad T470s connected to the docking station with analog audio input or output, the user does not receive any output sound. This problem does not affect the analog audio input or output in the ThinkPad laptop. (BZ#1548055)

Screen occasionally turns off when xrandr is executed

With the Nouveau driver, RANDR operations combined with heavy 3D load, such as querying the screen resolution, may cause screen flickering.
Flickering can be avoided by minimizing concurrent 3D and RANDR operations. Hence, query or resize the screen while 3D usage is minimal. (BZ#1545550)

HDMI and DP for 8th generation Intel Core processors not enumerating sound inputs

In Red Hat Enterprise Linux, support for alpha status hardware is disabled in the i915 driver by default. which causes that i915 never binds to the audio driver. As a consequence, HDMI and DP video and audio standards for 8th generation Intel Core processors do not enumerate sound inputs.
To work around this issue, boot your system with the i915.alpha_support=1 line added to the kernel command line. (BZ#1540643)

Tray icons are non-responsive for auto-started applications

The GNOME Shell TopIcons extension, which shows legacy tray icons on the top of the screen, does not work for auto-started applications: the tray icons are non-responsive. This bug does not include applications started after the GNOME Session starts.
As a workaround, follow this short procedure to restart the GNOME session: 1. press Alt + F2, 2. type r, 3. press Enter. (BZ#1550115)

Inconsistent panel color on login screen

When logging to a GNOME Classic session, suspending the laptop and resuming it again, the top panel on login screen is white, instead of black.
This problem does not affect GNOME Classic functionality. (BZ#1541021)

Additional displays are mirrored after attaching a VM guest

When opening a guest VM monitor and enabling an additional display from the remote-viewer menu, the content of the first display is mirrored to the newly attached one.
As a workaround, resize the remote-viewer frame of any display. The desktop environment will be extended to both displays and guest displays will be properly rearranged. (BZ#1539686)