Oh man I loved FrameMaker, I used it to write my thesis after spending a couple weeks fretting over and trying various features in Word and LaTeX. FrameMaker blew both of them away in terms of ease and ability to manage styles and table of contents, bibliography, equation editing, everything that normally makes writing a book hard.

I just went and read the history, and hadn’t realized that FrameMaker used to be UNIX and Mac only. Windows support was the last platform to be added, and after that UNIX and Mac support faded out. https://en.m.wikipedia.org/wiki/Adobe_FrameMaker#History