Configuration: Layer Rules

Overview

^{Since: 0.1.11}

Layer rules let you adjust behavior for individual layer-shell surfaces. They have match and exclude directives that control which layer-shell surfaces the rule should apply to, and a number of properties that you can set.

Layer rules are processed and work very similarly to window rules, just with different matchers and properties. Please read the window rules wiki page to learn how matching works.

Here are all matchers and properties that a layer rule could have:

layer-rule {
    match namespace="waybar"
    match at-startup=true

    // Properties that apply continuously.
    opacity 0.5
    block-out-from "screencast"
    // block-out-from "screen-capture"
}

Layer Surface Matching

Let's look at the matchers in more detail.

namespace

This is a regular expression that should match anywhere in the surface namespace. You can read about the supported regular expression syntax here.

// Match surfaces with namespace containing "waybar",
layer-rule {
    match namespace="waybar"
}

You can find the namespaces of all open layer-shell surfaces by running niri msg layers.

at-startup

Can be true or false. Matches during the first 60 seconds after starting niri.

// Show layer-shell surfaces with 0.5 opacity at niri startup, but not afterwards.
layer-rule {
    match at-startup=true

    opacity 0.5
}

Dynamic Properties

These properties apply continuously to open layer-shell surfaces.

block-out-from

You can block out surfaces from xdg-desktop-portal screencasts or all screen captures. They will be replaced with solid black rectangles.

This can be useful for notifications.

The same caveats and instructions apply as for the block-out-from window rule. Please read the block-out-from section in the window rules wiki page for more details.

// Block out mako notifications from screencasts.
layer-rule {
    match namespace="^notifications$"

    block-out-from "screencast"
}

opacity

Set the opacity of the surface. 0.0 is fully transparent, 1.0 is fully opaque. This is applied on top of the surface's own opacity, so semitransparent surfaces will become even more transparent.

Opacity is applied to every child of the layer-shell surface individually, so subsurfaces and pop-up menus will show window content behind them.

// Make fuzzel semitransparent.
layer-rule {
    match namespace="^launcher$"

    opacity 0.95
}