By the way, there are already services at least for automatic diffing: https://www.changedetection.com/ etc. (I don't know if this one is better than others, but this one has a memorable name; I have it pointed at one page, and get notifications from time to time, but never actually cared to dive in and check the diffs... :/ )

I wholeheartedly invite you to create a workflow on stacktile.io that demonstrates how to do it! :-)