There have been many. But none of them really successful, in the sense that they were more proof-of-concept, never fully feature-complete, or just not adopted b

There have been many. But none of them really successful, in the sense that they were more proof-of-concept, never fully feature-complete, or just not adopted by the community. See the list here: https://github.com/hoeck/schirm https://github.com/hoeck/schirm I think the most popular was TermKit (https://github.com/unconed/TermKit https://github.com/unconed/TermKit, https://news.ycombinator.com/item?id=30517205 https://news.ycombinator.com/item?id=30517205). Maybe the most successful such attempts is DomTerm (https://domterm.org https://domterm.org).