From Kayce Basques’ release notes for Chrome 64:1

Whoops! We originally scheduled this feature to launch in Chrome 64, but pulled it close to the deadline in order to smooth out some rough edges.

The ability for local overrides to persist between pages loads is going to be nothing short of amazing, especially for projects that have Hot Module Reloading. It is often the case that I will locally override the CSS for a page, get it looking exactly like I want it, then head over to my editor to make the changes for real. I’ll make the first change and then without thinking save the file. HMR internally refreshes the page, and I lose my other changes. I then have to continue making the rest of the changes in the editor from memory. Persistent local overrides solves that problem.

  1. There’s something the Chrome team doesn’t mention in its Chrome 64 update that’s worth mentioning: the San Francisco font looks different, in a good way. It’s now much closer to how the font appears in Safari. If you prefer doing your web reading in Safari because of its superior typography, that reason is going away. ↩︎