Firefox
Firefox is the recommended browser for ADL. It has strong ARM64 support, runs well under proot, and is available directly from the Ubuntu repositories. You do not need to hunt for third-party builds or worry about architecture mismatches.
Why Firefox?
Several factors make Firefox the best default choice for browsing in ADL:
- Native ARM64 packages — Ubuntu's repositories include a fully optimized ARM64 build
- Lower memory footprint — Firefox uses less RAM than Chromium-based browsers, which matters on devices with 4-8 GB
- Strong privacy defaults — built-in tracking protection reduces network requests and speeds up page loads
- Reliable rendering — Firefox handles software rendering gracefully when GPU acceleration is unavailable
Start with Firefox before trying other browsers. It has the fewest compatibility issues in a proot environment and requires the least configuration to get running.
Installation
Install Firefox from the Ubuntu repositories:
sudo apt update && sudo apt install firefoxFirefox appears in your application menu under Internet. You can also launch it from the terminal by running firefox.
If you are using a minimal Ubuntu installation that does not include a display server, make sure Termux:X11 is configured first. See the display setup guide for details.
Performance Configuration
Firefox works out of the box, but you can improve performance significantly by adjusting a few internal settings. Open a new tab and navigate to about:config, then accept the warning.
These settings are safe to modify, but changing random settings in about:config without understanding them can break your browser. Stick to the values listed here.
Recommended about:config Tweaks
| Setting | Value | Why |
|---|---|---|
gfx.webrender.all | false | Disables WebRender, which depends on GPU acceleration not available in proot |
layers.acceleration.disabled | true | Forces software compositing, preventing rendering glitches |
image.mem.surfacecache.max_size_kb | 131072 | Limits image cache to 128 MB to reduce memory pressure |
browser.sessionstore.interval | 60000 | Reduces session save frequency to once per minute, lowering disk I/O |
browser.tabs.unloadOnLowMemory | true | Automatically unloads background tabs when memory is low |
dom.ipc.processCount | 2 | Limits content processes to reduce memory usage |
After changing these settings, restart Firefox completely for all changes to take effect.
Disable Unnecessary Features
Reduce background resource usage by turning off features you likely do not need in an ADL environment:
# In about:config, set these values:| Setting | Value | Purpose |
|---|---|---|
toolkit.telemetry.enabled | false | Stops telemetry data collection |
datareporting.healthreport.uploadEnabled | false | Stops health report uploads |
extensions.pocket.enabled | false | Removes Pocket integration |
reader.parse-on-load.enabled | false | Disables reader view background parsing |
Essential Extensions
These extensions work well on ARM64 Firefox and improve the browsing experience:
| Extension | Purpose |
|---|---|
| uBlock Origin | Blocks ads and trackers. Reduces page weight and speeds up loading significantly |
| Dark Reader | Applies dark mode to all websites. Easier on your eyes when using a phone screen |
| Auto Tab Discard | Suspends inactive tabs to free memory |
| LocalCDN | Serves common libraries locally instead of fetching from CDNs |
uBlock Origin alone can reduce memory usage by 20-30% on ad-heavy sites. Install it first.
Fixing Common Issues
Font Rendering Problems
If web pages show missing characters, boxes, or incorrect fonts, you need to install font packages:
sudo apt install fonts-noto fonts-noto-cjk fonts-noto-color-emoji fonts-liberationThis installs comprehensive Unicode coverage including CJK characters and emoji.
Blank or Garbled Display
If Firefox opens but the window is blank or garbled, force software rendering:
export MOZ_X11_EGL=0 && firefoxTo make this permanent, add the export to your shell profile:
echo 'export MOZ_X11_EGL=0' >> ~/.bashrcHigh Memory Usage
Performance Tips
Follow these practices to keep Firefox responsive on constrained hardware:
Keep your open tab count below 5. Each tab consumes 50-150 MB of RAM depending on page complexity. On a device with 4 GB of RAM, 10 open tabs can consume half your available memory.
- Set a lightweight homepage — use
about:blankor a static HTML page instead of a content-heavy start page - Disable animations — set
ui.prefersReducedMotionto1in about:config - Clear cache regularly — Firefox's cache can grow large over time; set a cache limit in Preferences > Privacy & Security
- Use Reader View — on article-heavy sites, Reader View strips out heavy page elements and reduces memory usage per tab
- Avoid streaming video in multiple tabs — video decoding without hardware acceleration is CPU-intensive
Browser Alternatives
Firefox is the best default, but other browsers work in ADL depending on your needs.
Chromium works in ADL but typically uses 30-50% more memory than Firefox for the same set of tabs. If you need Chromium for web app compatibility, apply the same process count and telemetry tweaks described above — Chromium has similar settings under chrome://flags.