Customization

Otto's appearance is set from the config file: colour scheme, accent, wallpaper, fonts, icon theme, corner radius, window control side, and dock position and tint. This page shows what each of those does, on six configurations.

For each setting on its own, see Theming, Dock and Window Management.

A dark scheme with squared corners

accent_color = "#f2c300"
rounded_corners = false
window_controls_side = "right"

[dock]
colorize_icons = true
colorize_color = "#ffffff"
colorize_intensity = 1.0

The dock icons are tinted white. The tint is luminance × colour, so white is exactly a greyscale conversion: it preserves each icon's internal shading instead of flattening it to a silhouette.

All of these are in Settings as well, and all of them apply as soon as you save them.

A dock down the side

accent_color = "#7fd4e6"
window_controls_side = "left"
font_family = "Inter Display"

[dock]
position = "left"
colorize_color = "#7fd4e6"
colorize_intensity = 0.85

A side dock stacks its icons vertically, reserves screen width instead of height, magnifies along the pointer's vertical travel, and minimizes windows sideways into itself.

The compositor's own surfaces

accent_color and theme_scheme apply to the compositor's own surfaces as well: exposé, the workspace strip, the app switcher, and the brightness and volume indicators.

Desktop widgets and the app switcher

The panel on the left is an eww widget on the desktop layer: a wlr-layer-shell client, not an Otto feature.

The app switcher draws the same tinted icons as the dock, so a colourised dock does not leave the switcher looking like a different desktop. The colour and strength always come from [dock] — one desktop, one icon tint — and appswitcher.colorize_icons = false opts the switcher out.

A saturated tint

A saturated colorize_color sets a ceiling on each icon's luminance, so it needs light source icons. Applied to icons that are already dark it flattens them to silhouettes.

A light scheme

This uses the named brown accent rather than a hex literal, so it resolves to the light or dark palette's shade as the scheme changes.

The tint source is Papirus-Light here, even though the result is darker than the icons started. The filter maps each icon to its luminance re-coloured in colorize_color, then blends back toward the original by colorize_intensity, so what a light tint has to work with is the source icon's luminance.

What changes the look

Setting	Where	Effect
background_image, background_color	Theming	The wallpaper, and what shows if it fails to load
theme_scheme	Theming	Light or dark, for Otto's chrome and for GTK/Qt apps through the portal
accent_color	Theming	Selection, highlights and controls. A palette name or a hex literal
font_family	Theming	Otto's own interface type. Needs a restart
icon_theme	Theming	The source icons, before any tint
rounded_corners	Theming	Rounded or squared window corners
frosting	Theming	Blurred translucent chrome, or the same surfaces nearly opaque
window_controls_side	Window Management	Close/minimize/maximize on the left or right
dock.position	Dock	Bottom, left or right
dock.size, dock.magnification	Dock	How big, and whether icons grow under the pointer
dock.colorize_*	Dock	Tints every dock and switcher icon to one colour
workspaces.names	Workspaces	What the workspace strip is labelled with
workspaces.switch_duration, workspaces.switch_bounce	Workspaces	How fast, and how springy, the scroll between workspaces is

Almost everything here applies live: the wallpaper, the accent colour, the colour scheme, corners, frosting, the controls side, the icon and cursor themes and every dock.* setting all change what is on screen as you save them. Only the interface font and the interface scale need a restart — the font is baked into caches shared with the client toolkits, and the scale reaches every output and every maximized window. The settings app puts a badge beside those two and nothing else.

What Otto does not draw

Otto draws the dock, the top bar chrome, exposé and server-side window frames. Terminals, editors and status panels are separate clients and are themed on their own:

• Terminal — foot reads a palette from foot.ini. Otto implements ext-background-effect-v1, so blur=yes next to an alpha gets the blur from the compositor.
• Panels and widgets — eww and anything else speaking wlr-layer-shell sit on the desktop layer, behind windows and above the wallpaper. See Desktop Widgets.
• GTK applications — follow theme_scheme and the accent through the XDG Settings portal automatically. gtk_theme in Otto's config is recorded but not applied; set your GTK theme the usual way.