Theme Weaver by AlphaXP 404

Firefox lets an add-on repaint the browser: title bar, tabs, toolbar, address
bar, the main menu and panels, sidebar and new tab page. Theme Weaver turns
that into a design tool.

Design it live
• Every themeable part of Firefox, 37 in all, in one editor: hue, saturation,
lightness and opacity sliders, a hex field and a colour picker.
• The real window changes while you drag, and a full mock of Firefox in the
studio lets you click any part to edit it.
• Undo and redo everything.

Start from anywhere
• 20 hand-made presets, light and dark.
• From a photo: drop any picture and get a five-colour palette, plus the photo
as your header if you like.
• From this site: weave a theme from the colours of the page you're on.
• Surprise me: a random theme built on colour-harmony rules (analogous,
complementary, triad).

Readable by design
• A contrast guard checks all 14 text and icon pairs against WCAG AA and fixes
any that fail in one click.

It runs itself
• Day and night: two themes that take turns at fixed times, at your local
sunrise and sunset (pick a city, no location permission), or following your
system's light and dark mode.
• Per-window themes: make your work window unmistakable. They last until the
window closes. New private windows can wear their own theme too, once you
allow Theme Weaver in private windows.
• Ctrl+Shift+0 puts Firefox back to its default theme from anywhere.