How Picom applies blur?

[FrancoBujakiewicz]

How Picom blur transparent windows actually? I'm trying to XMobar get blurred, the bar has a variable named "alpha" to control transparency. I know the bar got blurred before, but I don't remember how. Wezterm terminal also has its own transparency and is blurred by Picom without problem. Why the terminal is blurred and the bar not? There's a thing named "depth" that I just know is related to all this (I don't understand the low-level there) for XMobar is 24 and in Wezterm 32.

I just have this in my Picom config:

   
   backend = "glx";

    corner-radius = 0;
    corner-radius-rules = [ "10:class_g = 'org.wezfurlong.wezterm'" ];

     fading = true;
     fade-in-step = 0.05;
     fade-out-step = 0.05;

     blur-method = "dual_kawase";
     blur-strength = 2.5;
     blur-background-include = [ "class_g = 'librewolf'" ];

Applying opacity to the bar with Picom and then blur works, but needs so much transparency to blur be notable. I want to apply blur to XMobar own transparency.

[CyberKite]

1. It's not possible. XMobar having a bit depth of 24 (8 for Red, 8 for Green, 8 for Blue) means it's not actually transparent. It likely just takes pixel data from the background and tints that a different color, so it looks transparent. You can either convince it to use a 32-bit depth (Red, Green, Blue, Transparency) or modify xmobar to blur the background by itself. Picom can't do much about that without weird heuristics that will break things

[FrancoBujakiewicz]

Well, that confirms it. Thank you anyway. I'll just don't blur the terminal then, I want both just transparent or both with blur.