Jupyter Collaboration has a history slider
Jupyter is really dominating now at university campus sites. I see it used for almost every course (at the least those that require data analysis via python).
This Jupyter (CRDT-based) extension appears to solve the BIGGEST HEADACHE I personally have with Jupyter(lab). Jupyter notebooks allow me to hack code/parameters too fluently, and I can't recover earlier positions in code/parameter space that produced interesting results.
Jupytext and git goes some way towards fixing that, but I don't save to git after every cut/paste of a parameter. This extension is effortless.
As a bonus, the extension appears to allow SubEthaEdit/GoogleDocs style collaboration too. (I haven't personally used that yet.)
Check it out.
Off topic: Tried to open the link and there seems to be Medium global outage. Have not seen that before.
Both collaboration and history are killer features. I'm going to have to try this out at work!