A lightweight, CEF-based web browser for Linux with off-screen rendering, a vertical sidebar UI, and built-in ad blocking.

• Off-Screen Rendering (OSR) -- All rendering composited through Cairo, no native CEF windows
• Vertical sidebar -- Tab list, bookmarks, downloads, navigation controls in a collapsible sidebar
• Custom titlebar -- Frameless window with minimize/maximize/close buttons
• Ad blocker -- EasyList + EasyPrivacy filter lists built in
• New tab page -- Search bar, shortcut grid, customizable backgrounds (solid/gradient/upload)
• Tab management -- Multiple tabs, incognito tabs, drag-to-reorder, Ctrl+Tab/Ctrl+W/Ctrl+T
• Per-domain zoom -- Zoom levels saved and restored per domain
• Session restore -- Tabs restored on restart
• Find in page -- Ctrl+F search with match count
• Bookmarks -- Add/remove with Ctrl+D, sidebar list
• History and Downloads pages -- orb://history/ and orb://downloads/
• Context menu -- Right-click with open in new tab, copy link, inspect element
• Keyboard shortcuts -- Ctrl+L (address bar), Ctrl+S (toggle sidebar), Ctrl+1-9 (switch tabs), F11 (fullscreen), F12 (DevTools)

• CMake 3.19+
• GCC/G++ with C++20 support
• GTK 3
• CEF (Chromium Embedded Framework) binary distribution

sudo pacman -S cmake gcc gtk3 pkgconf curl

sudo apt install cmake g++ libgtk-3-dev pkg-config curl

1. Download CEF binary distribution:

# Download from https://cef-builds.spotifycdn.com/index.html
# Select: Linux 64-bit -> Standard Distribution
wget 'https://cef-builds.spotifycdn.com/cef_binary_<VERSION>_linux64.tar.bz2'
tar xf cef_binary_*_linux64.tar.bz2
mv cef_binary_*_linux64 third_party/cef

2. Build:

./build.sh

Or manually:

mkdir -p build && cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
make -j$(nproc)

3. Run:

cd build && ./zen-browser

Tested on Linux x86_64 with NVIDIA GeForce RTX 4070 Laptop GPU. Same machine, same conditions.

Orb Browser uses CEF with off-screen rendering (OSR), single-process mode, and a minimal UI layer. The simplified rendering pipeline and lack of multi-process IPC overhead result in competitive graphics performance despite the OSR compositing cost.

src/
  main.cc                  -- Entry point
  browser/
    browser_app.cc         -- CEF app setup, scheme registration
    browser_client.cc      -- CEF client handlers (display, keyboard, download, etc.)
    browser_window.cc      -- GTK window, OSR compositing, input routing
    tab_manager.cc         -- Tab state management
    scheme_handler.cc      -- orb:// scheme (newtab, history, downloads)
    query_handler.cc       -- JS-to-C++ command bridge (cefQuery)
  blocker/
    filter_rules.cc        -- EasyList/EasyPrivacy parser
    request_filter.cc      -- Request interception
  ui/
    index.html             -- Sidebar chrome UI
    app.js                 -- Sidebar logic
    style.css              -- Sidebar styles
resources/
  easylist.txt             -- Ad block filter list
  easyprivacy.txt          -- Privacy filter list

• CEF off-screen rendering with Cairo compositing
• Vertical sidebar (tab list, navigation, bookmarks)
• Collapsible sidebar (Ctrl+S pin/unpin, hover to show)
• Custom frameless titlebar with minimize/maximize/close
• Tab management (open, close, switch, drag reorder)
• Incognito tabs
• New tab page with search bar and shortcut grid
• Customizable backgrounds (solid/gradient/image upload)
• Built-in ad blocker (EasyList + EasyPrivacy)
• Per-domain zoom persistence
• Session restore
• Find in page (Ctrl+F)
• Bookmarks (Ctrl+D)
• History page (orb://history/)
• Downloads page (orb://downloads/)
• URL autocomplete from history/bookmarks
• Context menu (open in new tab, copy link, inspect)
• Keyboard shortcuts (Ctrl+T/W/L/Tab, F11, F12)
• Configurable search engine (Google, DuckDuckGo, Bing, Brave)
• Configurable download directory
• Wayland support

• Windows support
• Extension support
• Sync (bookmarks, history, settings)
• Multiple profiles
• Reader mode
• Picture-in-picture
• Tab groups
• Custom themes/CSS
• Autofill (forms, passwords)
• Translation
• PDF viewer
• Print to PDF
• Notification support
• Hardware video acceleration

MIT