Dark Ritual is an ultra lightweight Firefox dark mode add-on that applies a site-wide dark theme that is very efficient and uses very few smart styling rules. It lets you control background color, text color, image/media brightness, and an optional daily schedule. I built it because Dark Reader was giving me performance issues in an old laptop and because I don't need so many features while also making a lot of calculations when the only thing I need is to comfortably look at the screen at night, I don't need the dark theme to be perfect at the cost of slowness and battery drain on my laptop. Features

Minimal stylesheet changes to reduce CPU usage
Fast dark-mode injection to reduce white flashes on navigation
Customizable background and text colors
Adjustable image/media brightness for darkened pages
Optional time-based activation with overnight schedule support
Instant updates across open tabs after changing settings
Visible keyboard focus styling for accessibility
Lightweight packaged assets and optimized add-on icons

Functionality Dark Ritual works by injecting a global stylesheet into pages and keeping that stylesheet in sync with your saved preferences. A background script maintains startup styling for active sessions, while the popup lets you enable or disable the add-on, choose colors, adjust media brightness, and configure an automatic schedule. Settings are stored locally in Firefox. The add-on does not declare any data collection. Permissions

storage: stores your preferences locally
alarms: checks schedule transitions once per minute
tabs: broadcasts updated settings to open tabs so changes apply immediately

Ultime version

Version 1.0.1

Versions plui vecjis

Version 1.0.0