“The software is amazing as you can see from this video”
Shows TeXmacs capabilities
Full comment
I'm not a TeXmacs developer but I am a fan. The software is amazing as you can see from this video: this video

32K views · Jun 9, 2021 · 3:41 · 3 HN recommenders · 5 mentions · discussed 2021–2023
A four-minute tour of the TeXmacs scientific editor, showing math typing, figures, citations, a drawing tool, document styles, HTML export, presentations and animations.
Why Hacker News points people here: Recommended as the quickest way to see what TeXmacs can do, as a WYSIWYG alternative to LaTeX.
“See here a short video describing its features”HN comment, 2023
“The software is amazing as you can see from this video”
Shows TeXmacs capabilities
I'm not a TeXmacs developer but I am a fan. The software is amazing as you can see from this video: this video
“Have you tried the WYSIWYG TeXmacs?”
Demo of WYSIWYG TeXmacs editor
Have you tried the WYSIWYG TeXmacs? (It's not based on TeX nor emacs but is inspired by both.) See: this video
“See here a short video describing its features”
Short overview of TeXmacs features
Have you considered TeXmacs (www.texmacs.org)? See here a short video describing its features: this video and the twitter feed for more examples: link
“you may want to check out what it can do”
Demo of programmable interactive typesetter
Not really what you asked for -- but there is an interactive modern typesetter that is programmable and works on trees. It's called TeXmacs - you may want to check out what it can do -- this video
“The closest thing for me is using TeXmacs”
Demo of TeXmacs as integrated technical editor
I'm sure there is so much room for improvement here. The closest thing for me is using TeXmacs: this video