Results in an optimized build with the addition of some previously not-included scripts and official userscripts.
Its build step is identical to what is currently in package.yml, but the install differs by adding a /usr/share/qutebrowser directory with scripts and userscripts subdirs, builds with the option --optimize=1 and does not include the 96x96 icon Solus includes.
The Makefile is recommended by upstream in the documentation and is used in the official Arch qutebrowser-git pkgbuild.