A reasonably complete KDE experience on Arch.

Arch Linux Setup

##install##
fdisk -l
cfdisk
mkswap /dev/sda2 -L Swap
swapon /dev/sda2
mkfs.ext4 /dev/sda1 -L Linux
mount /dev/sda1 /mnt
(wifi-menu)
pacstrap /mnt base linux linux-firmware
pacstrap /mnt os-prober grub dhclient
genfstab -p /mnt >> /mnt/etc/fstab
(add discard to the SSD entry in fstab)
arch-chroot /mnt
mkinitcpio -p linux
grub-mkconfig -o /boot/grub/grub.cfg
grub-install /dev/sda
### EFI ONLY ###
pacman -S efibootmgr
mkdir /boot/efi
mount /dev/sdX1 /boot/efi (assuming efi is on sdX1 as it typically is)
(put the EFI directory in fstab, mounted at /boot/efi)
(put Windows in fstab as well, if dual booting)
(enable OS-PROBER in /etc/default/grub)
grub-install --efi-directory=/boot/efi /dev/sda
grub-install --target=x86_64-efi --boatloader-id=grub_uefi --recheck
### END EFI ONLY ###
passwd
exit
umount /mnt
reboot

hostnamectl set-hostname myhostnamehere
timedatectl set-timezone US/Eastern
nano /etc/locale.gen
  (uncomment en_US and en_CA entries and save)
locale-gen
localectl set-locale LANG="en_US.UTF-8" LC_TIME="en_CA.UTF-8" LC_MEASUREMENT="en_CA.UTF-8"
nano /etc/environment
  LANG=en_US.UTF-8
  LC_TIME=en_CA.UTF-8
  LC_MEASUREMENT=en_CA.UTF-8
systemctl enable dhcpcd@eth0
timedatectl set-local-rtc true
pacman -S ntp
systemctl enable ntpd
reboot

useradd -m -g users -s /bin/bash user
passwd user
nano /etc/pacman.conf
  1. Under [options], add ParallelDownloads = 5
  2. Uncomment multilib (remove # in front)
pacman -Syu
pacman -S sudo
nano /etc/sudoers
  (configure your user)
su user
sudo pacman -S --needed bash-completion multilib-devel wget git jshon make pkg-config fakeroot autoconf automake patch alsa-oss alsa-plugins alsa-utils pulseaudio pulseaudio-alsa plasma-meta smplayer kde-gtk-config sshfs encfs ntfs-3g networkmanager networkmanager-openvpn yakuake konversation dhclient oxygen-icons-svg partitionmanager p7zip aspell aspell-en cabextract curl lib32-libcurl-compat dkms expac hunspell ispell smbclient samba sqlite unrar unzip zip mono wine wine_gecko wine-mono dosbox gstreamer gst-plugins-base gst-plugins-good gst-plugins-bad gst-plugins-ugly gst-libav firefox chromium kdialog sddm-kcm kde-applications libreoffice-fresh gufw xorg-xinit mesa lib32-libldap discover kdeconnect avahi nss-mdns packagekit-qt5 linux-firmware dialog netctl  pkgfile miniupnpc intel-ucode ktorrent oxygen-icons bat plocate geoip mariadb caprine
/usr/bin/appstreamcli refresh-cache --force --verbose
wget https://aur.archlinux.org/cgit/aur.git/snapshot/yay.tar.gz
tar zxvf yay.tar.gz
cd yay && makepkg
sudo pacman -U yay<tab>
yay
nano .gnupg/gpg.conf:
  add: keyring /etc/pacman.d/gnupg/pubring.gpg

When finished installing everything, free up disk space by removing package installation files: sudo rm /var/cache/pacman/pkg/*
sudo systemctl enable sddm
sudo systemctl enable NetworkManager
sudo mysql_install_db --user=mysql --basedir=/usr/ --ldata=/var/lib/mysql/
sudo systemctl enable mysqld
reboot

##Upgrade MySQL/MariaDB tables##
sudo mariadb-upgrade -u root -p

##Pulse Audio Settings##
sudo nano /etc/pulse/daemon.conf:
  exit-idle-time = -1
  allow-exit = no

sudo nano /etc/pulse/default.pa
  add comment: # load-module module-suspend-on-idle
  
  # Simultaneous output
  load-module module-alsa-sink device=hdmi:0
  # load-module module-alsa-sink device=hw:1,9 [aplay -l and test the devices to determine hw:x,y id]
  load-module module-combine-sink sink_name=combined
  set-default-sink combined
  
  # Reduce latency
  .ifexists module-udev-detect.so
  load-module module-udev-detect tsched=0 fixed_latency_range=yes fragments=1 fragment_size=15
  
sudo nano /etc/pulse/system.pa
  add comment: # load-module module-suspend-on-idle

##PipeWire Settings##
sudo cd /etc/pipewire
sudo mkdir media-session.d
sudo cp /usr/share/pipewire/media-session.d/media-session.conf /etc/pipewire/media-session.d
sudo nano /etc/pipewire/media-session.d/media-session.conf and comment out suspend-node
cd ~/.config && mkdir wireplumber && cd wireplumber/wireplumber.conf.d/ && mkdir wireplumber.conf.d && cd wireplumber/wireplumber.conf.d/
nano alsa-disable-suspension.conf and add:
monitor.alsa.rules = [
    {
        matches = [
            {
                node.name = "~alsa_input.pci.*"
            }
            {
                node.name = "~alsa_output.pci.*"
            }
        ]
        actions = {
            update-props = {
                session.suspend-timeout-seconds = 0
            }
        }
    }
]


##Mirrorlist$$
sudo nano /etc/pacman.d/mirrorlist-rankmirrors.conf and add:
COUNTRY=Canada

##Firewall##
sudo systemctl enable ufw
sudo systemctl start ufw
sudo ufw allow 1714:1764/udp
sudo ufw allow 1714:1764/tcp

##Yakuake##
Add the following to .bashrc for blurred background (also have to enable in shell Profile settings):
if [[ $(ps --no-header -p $PPID -o comm) =~ yakuake|emacs|emacs25 ]]; then for wid in $(xdotool search --pid $PPID); do xprop -f _KDE_NET_WM_BLUR_BEHIND_REGION 32c -set _KDE_NET_WM_BLUR_BEHIND_REGION 0 -id $wid; done fi

Add the following to .bashrc for cat with formatting and syntax highlighting:
alias cat="bat"
alias grep='grep --color=auto -i'
alias egrep='egrep --color=auto -i'
alias fgrep='fgrep --color=auto -i'

##Antivirus##
sudo pacman -S clamav
sudo systemctl enable clamd
sudo freshclam
sudo clamdscan --recursive=yes --infected /
sudo nano /etc/clamav/clamd.conf and add:
LogFile /var/log/clamav/clamd.log
LogTime yes
PidFile /run/clamav/clamd.pid
TemporaryDirectory /tmp
LocalSocket /var/lib/clamav/clamd.sock
User clamav
ExcludePath ^/proc/
ExcludePath ^/sys/
ExcludePath ^/dev/
ExcludePath ^/mnt
ExtendedDetectionInfo yes
ScanOnAccess yes
OnAccessMaxFileSize 10M
OnAccessMountPath /

**Log Limits**
sudo nano /etc/systemd/journald.conf and set:
SystemMaxUse=200M

mysql -u root
show variables like 'expire_logs_days';
SET GLOBAL expire_logs_days = 2;

##Filesharing##
sudo ufw allow 445/udp
sudo ufw allow 445/tcp
sudo ufw allow 135/udp
sudo ufw allow 135/tcp
sudo ufw allow 137:139/udp
sudo ufw allow 137:139/tcp
sudo ufw allow 5353/udp
sudo systemctl enable smbd
sudo systemctl enable nmbd
sudo nano /etc/samba/smb.conf and add the following:
[global]
   workgroup = WORKGROUP
   server string = HOSTNAME_HERE
   netbios name = HOSTNAME_HERE
   security = user
   map to guest = Bad User
   log file = /var/log/samba/%m.log
   max log size = 50
;   interfaces = 192.168.1.102/24
   dns proxy = no

   # Host resolution
   name resolve order = lmhosts bcast host wins
   client max protocol = NT1


[Share_Name_here]
   path = /share/path/here
   public = yes
   available = yes
   browsable = yes
   only guest = yes
   writable = yes


sudo nano /etc/nsswitch.conf:
   Change the hosts line to include mdns_minimal before resolve and dns

##Docker##
sudo pacman -S docker docker-compose
sudo nano /etc/environment:
TZ='America/New_York'
sudo groupadd docker
sudo usermod -aG docker ${USER}
sudo systemctl enable docker


##AMD Graphics##
sudo pacman -S --needed mesa mesa-libgl glu mesa-vdpau opencl-mesa libva-mesa-driver lib32-glu lib32-mesa lib32-mesa-vdpau lib32-libvdpau lib32-libva

If flickering occurs, create /etc/profile.d/kwin.sh containing:
#!/bin/sh
export KWIN_USE_BUFFER_AGE=0
export KWIN_TRIPLE_BUFFER=1


mplayer fails to start: sudo ln -s /usr/lib/libts-1.2.so.0 /usr/lib/libts-1.0.so.0

akonadi fails to start: touch ~/.local/share/akonadi/db_data/ib_logfile0

Cannot sign into Chromium:
nano ~/.config/chromium-flags.conf and add:
--oauth2-client-id=77185425430.apps.googleusercontent.com
--oauth2-client-secret=OTJgUOQcT7lO7GsGZq2G4IlT

GTK applications use KDE file picker
sudo nano /etc/environment and add:
GTK_USE_PORTAL=1

Firefox use KDE file picker
about:config
widget.use-xdg-desktop-portal.file-picker   set to 1