Firefox Focus is not available for Linux but there are plenty of alternatives that runs on Linux with similar functionality. The best Linux alternative is Mozilla Firefox, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 100 alternatives to Firefox Focus and many of them are available for Linux so hopefully you can find a suitable replacement. Other interesting Linux alternatives to Firefox Focus are Brave (Free, Open Source), Opera (Free), Chromium (Free, Open Source) and Pale Moon (Free, Open Source).
This is the hotdog web browser project. It's a web browser with its own layout and rendering engine, parsers, and UI toolkit! It's made from scratch entirely in golang. External dependencies are only OpenGL and GLFW, even go dependencies are kept to a minimum.