Is there maybe another collaborative word processing solution that supports this feature, that I've yet to find?
If the latter, you can use Draftback (described: [1], download: [2]) to get an Etherpad-style time slider in the text.
If you needed to preserve that view, you could screen record the playback. You could also dissect the Chrome extension and turn its rendering output into something else, a text revision with each change, suitable for checking into version control? I'm not sure how Draftback handles rich formatting, images, tables, or the like; you'd have to figure that out, too. You'd also have to match the checkins to the time spent doing the writing, or you'd miss out on the cadence of the writing. And is there even a tool that lets you visually scrub through a document's changes in git with a time slider or equivalent?
[1]: http://features.jsomers.net/how-i-reverse-engineered-google-...
[2]: https://chrome.google.com/webstore/detail/draftback/nnajoiem...
There are open solutions, such as the Collabora LibreOffice web version, that provides LO through the browser and has elements of collaboration.
https://www.collabora.com/about-us/open-source/open-source-p...
Well, overleaf, technically. You can sync it with a git repo.
- Edits LaTeX documents
- Text editor with live preview
- Git source control
The closest things I know of that resembles that are Confluence and Mediawiki.
There’s also Xwiki, but I haven’t yet tried it.