i3/.config/picom.conf

backend = "glx";
shadow = false;
blur-background = false;
fading = false;
vsync = true;
inactive-opacity = 1;
frame-opacity = 1;

wintypes:
{
  tooltip = { fade = false; shadow = false; full-shadow = false; };
  dock = { shadow = false; }
  dnd = { shadow = false; }
  popup_menu = { opacity = 1; }
  dropdown_menu = { opacity = 1; }
  notification = { opacity = 1; }
};