The title made me think this could actually layout and paint HTML, but I couldn't find anything remotely layout-related in the source tree. Then I found this comment saying even block sizing isn't done: <a href="https://github.com/lexbor/lexbor/issues/219#issuecomment-2073038107">https://github.com/lexbor/lexbor/issues/219#issuecomment-207...</a>. Looks like a nice groundwork, though. It's nice to see things like parsing and Unicode being part of the same source tree.