The interview mentions OmniFaces and PrimeFaces. These are not frameworks on top of JSF.
PrimeFaces is a component library. The entire purpose of JSF was to make such libraries possible. It introduced a component model with exactly the intend that a marketplace of components would appear.
This indeed happened. There's PrimeFaces, RichFaces, IceFaces, Trinidad, and a few others. They don't "fix problems" in JSF, but are what JSF was created to provide.
OmniFaces is a little different. It's a utility library. It does fixes small inconveniences in the JSF API, but it too is not a framework and makes use of the very extension points that JSF explicitly has provided.
Compare this to Eclipse. It's weird to say that JDT is a framework on top of Eclipse, since Eclipse was specifically made to host plug-ins.
