In the meantime, distributed archiving ftw, run your own archives with Webrecorder.io, ArchiveBox.io, SingleFile, kiwix.org, etc!
Is there a tool that downloads every website I visit locally and then, upon revisit, shows me my local copy for instant load, but does a diff in the background with the online version and asks me to show newer version only if there are differences?
Try https://github.com/WorldBrain/Memex, it has annotation and lets you review previously seen versions of a site as you're browsing.
Or check out some of the other options here:
- https://github.com/pirate/ArchiveBox/wiki/Web-Archiving-Comm...