Set picom dim to 0.

picom/picom.conf

@@ -124,7 +124,7 @@ opacity-rule = [
 ];
 
 # Dim inactive windows. (0.0 - 1.0)
-inactive-dim = 0.2;
+inactive-dim = 0.0;
 
 # Do not let dimness adjust based on window opacity.
 # inactive-dim-fixed = true;