The dark theme isn’t just a popular feature—it’s a smart one, especially for people who spend long hours in front of a screen. It helps reduce eye strain during night-time browsing and can even save battery on OLED displays. If you’re using Firefox, turning on the dark theme is quick and straightforward.
Whether you’re a night owl or simply love a cleaner, modern browsing look, this guide will walk you through three easy ways to activate dark mode in Firefox.
What is the Dark Theme and Why Should You Use It?
The dark theme, also called dark mode, swaps the typical light background for a darker one, with light text. This helps minimize glare and eye fatigue, particularly in low-light environments. On portable devices with OLED screens, it can also contribute to better battery life.
So beyond just looking sleek, the dark theme supports your comfort and your device’s efficiency.
How to Turn On the Dark Theme in Firefox
Here are three simple methods you can use to activate dark mode in Firefox:
Method 1: Use Firefox’s Built-in Theme Settings
Firefox comes with its own built-in dark theme, and enabling it only takes a few steps:
- Open Firefox on your desktop or laptop
- Click the menu button (☰) in the top-right corner
- Select “Add-ons and themes”
- In the left panel, click “Themes”
- Scroll to find the built-in “Dark” theme and click “Enable”
Your browser will instantly switch to a stylish dark look.
Method 2: Use Extensions for More Customization
Looking for more control over how dark mode behaves? Firefox’s extension store offers powerful tools:
- Go to addons.mozilla.org in Firefox
- Search for “dark mode” or “dark theme”
- Try extensions like Dark Reader or Midnight Lizard
- Click “Add to Firefox” and follow the installation steps
- After setup, customize brightness, contrast, and even specific site settings
For even more control across browsers, you might also explore tools like Dark Reader extension for Chrome and Firefox, which adapts non-dark websites into comfortable reading experiences.
Method 3: Use System-Wide Dark Mode Settings
Your computer’s dark theme can also influence how Firefox looks. Here’s how to activate it:
On Windows:
- Open Start > Settings
- Go to Personalization > Colors
- Under “Choose your default app mode”, select Dark
- Restart Firefox if it doesn’t switch automatically
On macOS:
- Open System Preferences
- Go to General
- Under “Appearance”, choose Dark
- Firefox will now match your system theme
Customization Options After Enabling Dark Mode
Once dark theme is on, you can take things further:
- Change Accent Colors: Choose highlight colors in Firefox’s “Themes” settings
- Enable Compact Mode: Go to Customize Toolbar to use a slimmer layout alongside dark mode
- Use Wallpapers or Extensions: Add-ons allow you to set dark-themed backgrounds on your homepage or new tabs
Troubleshooting Common Dark Theme Issues
Even simple settings can sometimes misbehave. Here’s how to fix dark mode hiccups:
1. Dark Theme Not Activating
Make sure Firefox is up to date:
- Open the menu
- Go to Help > About Firefox
- If an update is available, it will start downloading automatically
2. Websites Still Appear Too Bright
Install an extension like Dark Reader to override the website’s color scheme and apply a consistent dark background.
3. System Theme Not Syncing with Firefox
In Firefox:
- Go to Add-ons and Themes > Themes
- Ensure “Follow system theme” is selected instead of “Light” or “Default”
Why You Should Give Firefox’s Dark Theme a Try
Switching to dark mode is a small tweak that offers noticeable benefits. It reduces eye fatigue, saves a bit of battery, and gives your browser a polished look. Whether you’re working late, relaxing at night, or just prefer a darker interface, Firefox has made it easy to switch.
If you’re also interested in improving Firefox’s performance in other ways, check out how to change Firefox network timeout settings to make browsing smoother during slow connections.
