After installing Arch Linux
1. File manager
Dolphin is my goto file manager.
Install the dolphin pakcage and the needed themes.
sudo pacman -S dolphin breeze breeze-icons
Also configure file previews
sudo pacman -S kdegraphics-thumbnailers kimageformats qt5-imageformats kdesdk-thumbnailers ffmpegthumbs taglib
Finally, in order to configure Qt 5 applications under environments other than KDE Plasma, install the qt5ct-kde AUR package, and use Breeze Dark as the color theme & icon theme.
2. Video playing
This section is mainly about playing videos via VLC. The configuration
may not apply to other players such as mpv.
2.1. GPU Driver
Install this for hardware acceleration:
sudo pacman -S libva-intel-driver
2.2. RTSP streaming
If an error occurs when trying to open RTSP streaming via VLC, install
live-media:1
sudo pacman -S live-media
Note that mpv does not this to open RTSP.