Use Clang compiler instead of GCC Integrate with gnome-base/gnome-shell search Force-enable hardware-accelerated rendering (Mozilla bug 594876) Enable unified build - combines source files to speed up build process, but requires more memory Enable libproxy support Use media-libs/openh264 for H.264 support instead of downloading binary blob from Mozilla at runtime Add support for profile-guided optimization using gcc-4.5, for faster binaries. This option will double the compile time. Enable support for the media-sound/sndio backend Use the system-wide media-libs/dav1d and media-libs/libaom library instead of bundled. Use the system-wide media-libs/harfbuzz and media-gfx/graphite2 instead of bundled. Use the system-wide dev-libs/icu instead of bundled. Use the system-wide media-libs/libjpeg-turbo instead of bundled. Use the system-wide dev-libs/libevent instead of bundled. Use the system-wide media-libs/libvpx instead of bundled. Use system media-video/pipewire for WebRTC and screencast instead of bundled one Use the system-wide media-libs/libpng instead of bundled (requires APNG patches) Use the system-wide media-libs/libwebp instead of bundled. Sandbox certain third-party libraries through WebAssembly using RLBox