Software

• Spell checking
• Fonts
• Polkit
• Firefox
• Google Chrome
• Discord
• Blu-ray
• Node.js (nvm)
• Kernel‑based Virtual Machine (KVM)
• Folding@Home
• Timeshift
• GNOME Flatpaks

Spell checking

Hunspell is a spell checker and morphological analyzer library used by Firefox, Thunderbird, Chromium, LibreOffice and more.

Install the following packages to enable system-wide spell checking and hyphenation support (add languages for hunspell and hyphen at your discretion):

pacman -S hunspell hunspell-de hunspell-en_US hyphen hyphen-de hyphen-en 

Fonts

For most desktop environments, a sufficient number of fonts is installed as dependencies. However, there's several additional packages for different styles and writing systems (latin vs. non-latin scripts). Arch Wiki has an extensive list of available fonts in both the repositories and the AUR. Installing the Noto font family also provides a vast coverage over a large array of scripts.

Configuration

Most applications read the font configuration provided by the fontconfig library. These configurations are written in XML and read from several different locations.

Configuration files are read in and applied in lexical order. If you need rules applied in a specific order, make sure to prepend them with 2-digit numbers in the order you need.

A minimal fontconfig configuration file contains these headers:

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
<fontconfig>

  <!-- settings go here -->

</fontconfig>

Some font packages come with pre-defined rule sets, which are installed to /usr/share/fontconfig/conf.avail/. To apply them, it's best to create symbolic links to them in their respective drop-in configuration directories.

To apply them system-wide, link them from the /etc/fonts/conf.d directory:

cd /etc/fonts/conf.d
sudo ln -s /usr/share/fontconfig/conf.avail/70-no-bitmaps-except-emoji.conf

To apply them only to the currently logged in user, link them in the $XDG_CONFIG_HOME/fontconfig/conf.d directory:

HINT: The environment variable $XDG_CONFIG_HOME should point to the .config sub-directory in your home directory. If it doesn't, use $HOME/.config instead for the examples or set it with export.

mkdir $XDG_CONFIG_HOME/fontconfig/conf.d
ln -s /usr/share/fontconfig/conf.avail/70-no-bitmaps-except-emoji.conf $XDG_CONFIG_HOME/fontconfig/conf.d

Emoji Fonts

There are a few emoji fonts available on Arch.

Install your selected emoji font:

pacman -S noto-fonts-emoji

Applications requesting emoji to be displayed should pick up on the font after restarting them.

NOTE: KDE sometimes applies emoji fonts incorrectly, either not showing them at all or showing the outline symbol version from a different font. You can fix this by installing noto-color-emoji-fontconfig from the AUR and creating a symbolic link to the configuration file as shown above.

Polkit

polkit is an application-level toolkit for defining and handling the policy that allows unprivileged processes to speak to privileged processes: It is a framework for centralizing the decision making process with respect to granting access to privileged operations for unprivileged applications.

Custom rules

Mount disks as user

Edit/create /etc/polkit-1/rules.d/50-udisk.rules

// Original rules: https://github.com/coldfix/udiskie/wiki/Permissions
// Changes: Added org.freedesktop.udisks2.filesystem-mount-system, as this is used by Dolphin.

polkit.addRule(function(action, subject) {
  var YES = polkit.Result.YES;
  // NOTE: there must be a comma at the end of each line except for the last:
  var permission = {
    // required for udisks1:
    "org.freedesktop.udisks.filesystem-mount": YES,
    "org.freedesktop.udisks.luks-unlock": YES,
    "org.freedesktop.udisks.drive-eject": YES,
    "org.freedesktop.udisks.drive-detach": YES,
    // required for udisks2:
    "org.freedesktop.udisks2.filesystem-mount": YES,
    "org.freedesktop.udisks2.encrypted-unlock": YES,
    "org.freedesktop.udisks2.eject-media": YES,
    "org.freedesktop.udisks2.power-off-drive": YES,
    // Dolphin specific
    "org.freedesktop.udisks2.filesystem-mount-system": YES,
    // required for udisks2 if using udiskie from another seat (e.g. systemd):
    "org.freedesktop.udisks2.filesystem-mount-other-seat": YES,
    "org.freedesktop.udisks2.filesystem-unmount-others": YES,
    "org.freedesktop.udisks2.encrypted-unlock-other-seat": YES,
    "org.freedesktop.udisks2.eject-media-other-seat": YES,
    "org.freedesktop.udisks2.power-off-drive-other-seat": YES
  };
  if (subject.isInGroup("storage")) {
    return permission[action.id];
  }
});

Firefox

Install Firefox via these packages (adjust for your desired locale):

pacman -S firefox firefox-i18n-de

Hardware Acceleration

Utilizing GPU hardware accelerated decoding of video content results in smoother playback of HD/4K content, while reducing CPU load and power draw (important to save on battery on laptops).

To ensure Firefox uses hardware decoding verify the following:

• The necessary VA-API drivers are installed (see: Graphics Cards)
• Navigate to about:support and verify that Compositing says WebRender (WebRender Software will not work)

Verify hardware video decoding

To verify Firefox is actually using VA-API to decode video you can launch it with the following command:

MOZ_LOG="FFmpegVideo:5" firefox 2>&1 | grep 'VA-API'

Start playing some video in Firefox and watch the logs on your terminal. If your log output reads something like the following video decoding via VA-API is working.

[RDD 97685: MediaPDecoder #1]: D/FFmpegVideo FFVPX: Initialising VA-API FFmpeg decoder
[RDD 97685: MediaPDecoder #2]: D/FFmpegVideo FFVPX:   VA-API FFmpeg init successful
[RDD 97685: MediaPDecoder #2]: D/FFmpegVideo FFVPX: Choosing FFmpeg pixel format for VA-API video decoding.
[RDD 97685: MediaPDecoder #1]: D/FFmpegVideo FFVPX:   VA-API FFmpeg init successful
[RDD 97685: MediaPDecoder #2]: D/FFmpegVideo FFVPX: VA-API Got one frame output with pts=0 dts=0 duration=40000 opaque=-9223372036854775808
[RDD 97685: MediaPDecoder #1]: D/FFmpegVideo FFVPX: Initialising VA-API FFmpeg decoder
[RDD 97685: MediaPDecoder #1]: D/FFmpegVideo FFVPX:   VA-API FFmpeg init successful
[RDD 97685: MediaPDecoder #1]: D/FFmpegVideo FFVPX: VA-API Got one frame output with pts=40000 dts=40000 duration=40000 opaque=-9223372036854775808
[RDD 97685: MediaPDecoder #2]: D/FFmpegVideo FFVPX: VA-API Got one frame output with pts=80000 dts=80000 duration=40000 opaque=-9223372036854775808
[RDD 97685: MediaPDecoder #2]: D/FFmpegVideo FFVPX: VA-API Got one frame output with pts=120000 dts=120000 duration=40000 opaque=-9223372036854775808

Customization

ATTENTION: Firefox version 147 introduced support for the XDG Base Directory Specification. Firefox will not migrate old profiles to the new directory structure. If you've set up Firefox before version 147, the previous location for all things Firefox remains ~/.mozilla/. This article assumes a fresh install.

Most customizations can be done in about:config from the browser UI. Settings that deviate from defaults are saved to ~/.config/mozilla/firefox/<user-profile>/prefs.js.

It is possible to pre-set certain settings in a separate user.js file in the same directory to override defaults. Both files have the same syntax:

user_pref("setting.key.goes.here", value)

Autoplay in background

Firefox prevents autoplay for media of tabs that aren't currently active, which causes apps like Plex to take very long to skip to the next track after the current one has ended. The following setting in about:config can be used to disable this behavior:

Or via user.js:

user_pref("media.block-autoplay-until-in-foreground", false)

KDE Plasma Integration

For better integration of Firefox into the KDE Plasma desktop, install the Plasma Integration add-on either via the Mozilla Add-on page. It enables rich notifications support and download progress integration into the notification area of KDE Plasma.

To prevent duplicate entries in the Media Player widget or tray icon, set media.hardwaremediakeys.enabled to false. This disables the media entry from Firefox itself and only uses the one from the Plasma integration add-on.

Or via user.js:

user_pref("media.hardwaremediakeys.enabled", false)

XDG Portal Integrations

By default, Firefox uses GTK file and print dialogs, even on KDE. To change this to KDE native dialogs navigate to about:config and change the appropriate widget.use-xdg-desktop-portal settings to 1 (default is 2 which equates to auto-detection).

The settings are as follows:

Or via user.js:

user_pref("widget.use-xdg-desktop-portal.file-picker", 1);
user_pref("widget.use-xdg-desktop-portal.location", 1);
user_pref("widget.use-xdg-desktop-portal.mime-handler", 1);
user_pref("widget.use-xdg-desktop-portal.open-uri", 1);
user_pref("widget.use-xdg-desktop-portal.settings", 1);

Disable AI Integrations

Mozilla introduced multiple AI integrations, despite user pushback. To disable these set the following settings in user.js:

user_pref("browser.ml.chat.enabled", false);
user_pref("browser.ml.chat.menu", false);
user_pref("browser.ml.chat.page.footerBadge", false);
user_pref("browser.ml.chat.page.menuBadge", false);
user_pref("browser.ml.chat.page", false);
user_pref("browser.ml.enable", false);
user_pref("browser.ml.linkPreview.enabled", false);
user_pref("browser.ml.pageAssist.enabled", false);
user_pref("browser.ml.smartAssist.enabled", false);
user_pref("browser.search.visualSearch.featureGate", false);
user_pref("browser.tabs.groups.smart.enabled", false);
user_pref("browser.tabs.groups.smart.userEnabled", false);
user_pref("browser.urlbar.quicksuggest.mlEnabled", false);
user_pref("extensions.ml.enabled", false);
user_pref("pdfjs.enableAltText", false);
user_pref("places.semanticHistory.featureGate", false);
user_pref("sidebar.revamp", false);

Google Chrome

Install Google Chrome from AUR:

yay -S google-chrome

Tweaks

To enable hardware accelerated video decoding (with open source drivers) create a file at ~/.config/chrome-flags.conf and add the following line in it:

--enable-features=VaapiVideoDecoder

Additionally, if you need to be able to share your screen wie WebRTC, you need to add the following line as well:

--enable-usermedia-screen-capturing

Furthermore, visit chrome://flags and set the following options to further tweak performance (use the search field to filter):

Discord

Discord is a proprietary, cross-platform, all-in-one voice and text chat application.

Install Discord from the repositories:

pacman -S discord 

Or the official Flatpak app:

flatpak install com.discordapp.Discord

Rich Presence with Flatpak

Discord provides a Unix socket file that games and applications use in order to show what game or media is currently being played.

The Flatpak version creates this socket in a different location than the repo package version. In order for games and apps to still be able to communicate with the Discord app, a symbolic link needs to be created in the usual place, pointing to the location of the socket file of the Flatpak version.

The most straightforward way is to create a symbolic link with a single command:

ln -sf $XDG_RUNTIME_DIR/{app/com.discordapp.Discord,}/discord-ipc-0

However, since $XDG_RUNTIME_DIR is a tmpfs in RAM, its contents will be discarded if the system is shut down or rebooted. To fix this, systemd-tmpfiles can be used to automatically re-create the link every time you log into your desktop session.

Create the directory user-tmpfiles.d in your user's .config directory:

mkdir -p ~/.config/user-tmpfiles.d

In the newly created directory, create a new config file:

nano ~/.config/user-tmpfiles.d/discord-ipc.conf

systemd-tmpfiles uses the information in the config file to create temporary files as long as the user is logged in and remove them once the user logs out.

The fields in this file are space separated. The fields are as follows:

In order for the link to point to the Discord socket of the Flatpak version, the resulting config file should look have this line:

L %t/discord-ipc-0 - - - - app/com.discordapp.Discord/discord-ipc-0

This will create a symbolic link at /run/user/1000/discord-ipc-0 pointing to the actual socket file at /run/user/1000/app/com.discordapp.Discord/discord-ipc-0 where the Flatpak version of Discord is listening on incoming connections from other apps and games.

systemd-tmpfiles will not pick up on the new config file automatically, it will however read it upon next log-in. Alternatively, run systemd-tmpfiles --user --create manually to have systemd-tmpfiles create the link for you.

Blu-ray

Playback

In order play Blu-Rays install the following packages:

sudo pacman -S libbluray libaacs

Additionally, a KEYDB.cfg file is needed. Download it from the FindVUK Online Database

Extract the ZIP to ~/.config/aacs/:

unzip keydb_eng.zip -d ~/.config/aacs/

After that use any Blu-Ray capable playback software, e.g. vlc bluray:///dev/sr0 to play back Blu-Rays.

Ripping

In order to rip Blu-Rays install MakeMKV from the AUR:

yay -S makemkv

MakeMKV requires the sg (SCSI generic (sg) driver) kernel module to be loaded in order to recognize the drive. To load the module temporarily:

sudo modprobe sg

To have the kernel load the module on each boot:

echo sg | sudo tee > /etc/modules-load.d/sg.conf

Node.js (nvm)

Use the Node Version Manager (nvm) to install Node.js into your current user's path and switch Node.js versions on the fly.

Install nvm via the AUR:

yay -S nvm

Include the init script /usr/share/nvm/init-nvm.sh into your shell configuration to load it each time you start your terminal:

# bash
echo 'source /usr/share/nvm/init-nvm.sh' >> ~/.bashrc

# zsh
echo 'source /usr/share/nvm/init-nvm.sh' >> ~/.zshrc

Restart your terminal to reload all init scripts and you should be able to use nvm to install a Node.js version of your choice:

nvm install 12

Migrating globally installed npm packages

When you install and switch to a different nvm managed version of Node.js (nvm install 14 or nvm use 16) you may find that your globally installed npm packages (e.g. svgo) are no longer available until you switch back to the specific version of Node.js you have been using before the upgrade or switch.

This is because globally installed npm packages are installed for the specific version of Node.js you happen to be using at the time of installation and placed in a directory i.e. ~/.nvm/versions/node/v16.14.0/lib/node_modules. When you install a different version, e.g. 17.2.0 the path to your Node.js installation changes to ~/.nvm/versions/node/v17.2.0/lib/node_modules.

Use the --reinstall-packages-from=<version> option to carry over globally installed packages to the new Node.js installation.

You can either pass a specific version you want to reinstall globally installed packages from or use bash string expansion to reinstall from the currently active one in use:

nvm install <new version> --reinstall-packages-from=<old version>

nvm install 17 --reinstall-packages-from=$(node -v)

Kernel‑based Virtual Machine (KVM)

Kernel‑based Virtual Machine (KVM) is a full virtualization solution built into the Linux kernel. User space tools such as libvirt provide a standardized way to interface with virtualization engines, not only KVM but also Xen, OpenVZ and VirtualBox. Graphical tools like virt‑manager allow for user-friendly management of virtual machines running on the local machine or on remote hosts running libvirt.

Preparation

KVM supports a wide range of guests, including Linux, BSD and even Windows. It's architecture allows for near-metal performance. To achieve this KVM utilizes hardware assisted virtualization technologies on the host machine's CPU (Intel VT, AMD-V).

On most desktop systems, these virtualization technologies are not enabled out of the box. To check if virtualization technologies are available on your system, use lscpu:

LC_ALL=C.UTF-8 lscpu | grep Virtualization

This will query the CPU's specifications and filter the output for the relevant virtualization feature section.

If the command produces no output, it indicates the system's CPU either does not support hardware assisted virtualization (unlikely if the machine's CPU was purchased in the last 10 years) or the feature is disabled in the machine's firmware options.

Hardware assisted virtualization technologies are a pre-requisite to being able to use KVM. Refer to your mainboard's user manual to learn how to enable the option.

NOTE: Settings related to CPU virtualization features can sometimes be found in the "Overclocking" section of your firmware settings.

Also consider enabling IOMMU (Intel VT-d, AMD-Vi) for direct device pass-through.

NOTE: On Intel-based systems, unless your kernel has the config option CONFIG_INTEL_IOMMU_DEFAULT_ON set (default is unset) you will also have to explicitly add intel_iommu=on to your kernel boot parameters.

Installation

The most common way to start using KVM is by installing QEMU, a generic and open source machine emulator and virtualizer. It utilizes KVM to achieve very good performance and can even emulate a different architecture from the one in the host machine. Though KVM is the most commonly used hypervisor for QEMU, it can also utilize other hypervisors, such as Xen, OpenVZ or VirtualBox.

Arch Linux offers several levels of completeness of the QEMU suite of emulators:

• qemu-full: installs the entirety of QEMU tools and libraries, capable of emulating many different systems and architectures.
• qemu-desktop: installs the essentials for running a QEMU environment for emulating x86_64 systems to run virtual machines on a desktop computer.
• qemu-base: the most basic QEMU environment intended for use on servers and headless environments.

Install the package that applies best for your use-case, e.g. if you plan on running virtual machines on your desktop computer:

sudo pacman -S qemu-desktop

QEMU itself does not provide graphical tools to set up and manage virtual machines. This is where libvirt comes in: it provides APIs for user-facing applications to offer graphical front-ends to users. One such application is virt-manager available from Arch repositories:

sudo pacman -S virt-manager libvirt

By default, only root can interface with KVM and thus the full system emulator provided by QEMU and libvirt will require elevated privileges every time you intend to run virtualized environments.

To allow your user to use virtual machines powered by KVM and libvirt add it to the libvirt group:

sudo usermod -aG libvirt $USER

NOTE: The change will apply after logging out and back in again, or after a reboot. Feel free to continue the steps below until you actually start using QEMU.

Then, enable and start the libvirt daemon:

sudo systemctl enable --now libvirtd

Networking

For virtual machines to have network access, a network bridge needs to be created.

This is relatively easily achieved with nmcli, the CLI tool for NetworkManager:

# Create the new bridge interface
nmcli connection add \
      type bridge \
      ifname br0 \
      con-name "Bridge" \
      stp no

# Determine the current default route network adapter and add it to the bridge
DEFAULT_IF=$(ip r s default | awk '{print $5}')
nmcli connection add \
      type bridge-slave \
      ifname "$DEFAULT_IF" \
      con-name "Ethernet" \
      master br0

# Disable the old wired connection and bring up the bridge
nmcli connection down "Wired Connection 1"
nmcli connection up "Bridge"

To easily select the bridge network in a guest's network settings, create a small libvirt network XML definition file, e.g. as br0.xml:

<network>
  <name>br0</name>
  <forward mode='bridge'/>
  <bridge name='br0'/>
</network>

Import the definition file and set the network to autostart:

sudo virsh -c qemu:///system net-define br0.xml
sudo virsh -c qemu:///system net-autostart br0

Storage

Storage under libvirt is defined as pools which can be any of the following:

• a local directory
• a dedicated disk
• a pre-formatted block device
• an iSCSI target
• an LVM group
• a multi-path device enumerator (RAID device)
• an exported network directory
• a ZFS pool

The default storage pool is defined as a local directory at /var/lib/libvirt/images. This is where libvirt will store disk images for guests.

sudo chattr +C /var/lib/libvirt/images

Storage pools can be created from within virt-manager or by writing custom XML definitions and importing them with virsh, in the case that the storage pool type is not exposed through the GUI or you need more fine-grained control over the specifications of the pool.

If you have a remote storage location that holds disk images, i.e. an exported NFS share with ISO images, it's possible to add it as a pool and mount it into the guest without the need to copy the images to your computer first.

The XML definition for a storage pool, named remote-iso.xml for example, could look something like this:

<pool type="netfs">
  <name>iso</name> <!-- name of the pool -->
  <source>
    <host name="dragonhoard"/> <!-- hostname/IP of remote machine -->
    <dir path="/mnt/user/downloads/ISOs"/> <!-- full path to images on remote machine -->
    <format type="auto"/>
  </source>
  <target>
    <path>/var/lib/libvirt/images/iso</path> <!-- mount point on local machine -->
  </target>
</pool>

In order for libvirt to successfully mount the network share, the mount point must exist prior to activating the pool:

sudo mkdir -p /var/lib/libvirt/images/iso

Finally, import the pool definition and set it to autostart:

sudo virsh -c qemu:///system pool-define remote-iso.xml
sudo virsh -c qemu:///system pool-autostart iso

When creating new virtual machines, the contents of the remote location are now easily selectable from within virt-manager's creation wizard.

Folding@Home

Help scientists studying Alzheimer's, Huntington's, Parkinson's, and SARS-CoV-2 by simply running a piece of software on your computer. Add your computer to a network of millions of others around the world to form the world's largest distributed supercomputer.

Installlation

yay -S foldingathome opencl-amd

Configuration

Run FAHClient --configure as root to generate a configuration file at /etc/foldingathome/config.xml:

cd /etc/foldingathome
FAHClient --configure

Then start/enable the foldingathome.service systemd unit. NVIDIA users should also enable the foldingathome-nvidia.service systemd unit.

Example Configuration

<config>
  <!-- Slot Control -->
  <power v='FULL'/>

  <!-- User Information -->
  <passkey v='1234567890'/>
  <team v='45032'/>
  <user v='Registered_User_Name'/>

  <!-- Folding Slots -->
  <slot id='0' type='CPU'/>
  <slot id='1' type='GPU'/>
</config>

Timeshift

IMPORTANT: Timeshift is not a backup tool! It only creates local snapshots of the system to roll back changes to the system. Do not rely on this mechanism to keep your data safe! Timeshift deletes the oldest snapshot when a new one is created and the maximum number of snapshots is reached. Furthermore, if the underlying file system is corrupted, the snapshots will be, too! Use a proper backup tool to keep your data safe on external data storage!

Timeshift helps create incremental snapshots of the file system at regular intervals, which can then be restored at a later date to undo all changes to the system.

It supports rsync snapshots for all filesystems, and uses the built-in snapshot features for Btrfs drives configured to use the @ and @home subvolume layout for root and home directories respectively.

Installation

Timeshift is available from the Arch repos. It uses cron to make regularly scheduled backups. Install Timeshift with a cron daemon, e.g. cronie:

pacman -S timeshift cronie

Start and enable the cron scheduler for Timeshift to take regular snapshots:

sudo systemctl enable --now cronie

Finally, start Timeshift and complete the first time setup.

Automatic snapshots on system changes

In addition to Timeshift's periodic spanshots, timeshift-autosnap provides a pacman hook to create a manual snapshot every time packages are installed, upgraded or removed.

Install timeshift-autosnap from the AUR:

yay -S timeshift-autosnap

By default timeshift-autosnap only keeps 3 snapshots. To change this, edit /etc/timeshift-autosnap.conf and either set deleteSnapshots to false to never delete any snapshots or increase the number of maxSnapshots:

skipAutosnap=false
deleteSnapshots=true
maxSnapshots=7
updateGrub=true
snapshotDescription={timeshift-autosnap} {created before upgrade}

Prevent excessive snapshotting when using yay

By default, when installing or updating multiple packages from the AUR, yay first builds a package and immediately calls pacman to install it, before building and installing the next one on its list. This also means that the timeshift-autosnap hook is triggered for each individual AUR package built by yay, including dependencies also installed from the AUR.

This can have undesireable side-effects:

• yay will cause timeshift-autosnap to reach the maxSnapshots limit very quickly when installing multiple packages from the AUR, leaving you with snapshots with little to no meaningful changes between them
• if deleteSnapshots is set to false the amount of snapshots might quickly exhaust the usable space on the drive

To prevent this it is recommended to configure yay to:

1. not remove make dependencies after successfully built packages are installed
2. build all AUR packages first, install them all later
3. install AUR packages together with regular repo packages

By calling yay with the --save parameter, any options passed to it will be saved in a configuration file, e.g.:

yay --noremovemake --batchinstall --combinedupgrade --save  

Next time you use yay to install, upgrade or remove packages it will read the generated config file at ~/.config/yay/config.json and apply the options automatically without having to specify them during use.

GNOME Flatpaks

Core apps

Internet

Multimedia

Productivity

Games

Tools

Software development