Ladybird is lucky in that it has someone who knows how important marketing is, even for opensource projects. There are other opensource browser engine projects languishing because of lack of PR, patronage and / or volunteers. For e.g. NetSurf https://www.netsurf-browser.org/ - website is outdated because of lack of volunteers but the project has active development - https://source.netsurf-browser.org/netsurf.git/ (already has partial support for CSS3, and Flex layout). It can develop into a great alternative if it had some more volunteers. Servo (https://servo.org/) is another project but it has some decent PR because of its Rust codebase and the Rust PR team. There's the Goanna browser engine too ( http://www.palemoon.org/ ) but, like Mozilla Gecko, the project isn't truly modular to offer a stand-alone browser engine as Goanna also strives to be an XUL renderer.