picom

• arch wiki - picom
• install picom

pacman -S picom

• edit config at ~/.config/picom/picom.conf
• use opengl

# use OpenGL as the rendering backend
backend = "glx";

• screen tears without fading, default fading animation is too slow

# without fading, some screen tears
fading = true;
# speed up default fade speed
fade-delta = 3;

• transparency for aesthetic

# make inactive windows slightly transparent
inactive-opacity = 0.9;

• exclude i3lock from transparency to prevent desktop leaking and exclude floating windows

opacity-rule = [
    # exclude screensaver (i3lock) window
    "100:class_g = 'i3lock'",
    # exclude floating windows
    "100:I3_FLOATING_WINDOW@:c",
];