Themes

Themes

Themes are data, not code. Every color, size, type size and timing of the window's chrome comes from one JSON file, themes/default.json. Edit it while the window is open and the chrome follows.

Where the theme comes from

• themes/default.json beside the executable, else in its parent directory
• --theme <file.json> on the command line
• Every token has a built-in default; a missing or malformed token falls back to it, and each problem is named

The tokens

Colors — chrome-background, chrome-text, chrome-text-muted, chrome-border, tab-active-background, tab-inactive-background, tab-hover-background, address-background, address-text, address-border, accent, selection, find-highlight, find-current, hint-background, hint-text, button-hover-background, button-disabled-text, status-background, status-text, content-background, secure-indicator, insecure-indicator

Metrics — tab-strip-height, tab-height, tab-max-width, tab-min-width, tab-corner-radius, tab-gap, toolbar-height, address-height, address-corner-radius, button-size, button-corner-radius, padding, border-width, status-height, find-height, devtools-height, scroll-step, tab-icon-size

Type — font-size, tab-font-size, status-font-size

Timings — tab-hover, tab-switch

New tab ("new-tab": { … }) — backgrounds, a folder of pictures (PNG, JPEG, GIF or BMP) written relative to the theme file, which the new-tab page rotates through in name order; rotate, how long each picture stays before the next fades in, in milliseconds (0 never rotates; 20000 by default). A theme that names no folder gets a gradient of its own colors.

Colors are written as #rrggbb or #rrggbbaa.

How it is held honest

A unit test asserts that the shipped themes/default.json equals the built-in defaults token for token, so the file and the code cannot drift apart. The chrome goldens in CI (see Testing) are rendered from the same file.