Google's John Mueller said on Twitter that Google almost certainly cannot index a page that requires cookies. He said if you want Google to index the page, make sure to "remove the dependency" on cookies.
This is really not news to SEOs, we reported this many times, most recently when John Mueller said Google crawls the stateless web and that although Google cannot index pages that require cookies, Google is able to detect if cookies are required on the page.
John write this on Twitter:
We almost never use them. If you need cookie support to view a page, it's almost certain that we wouldn't be able to index it. If you notice it in an audit, fix it (remove the dependency), don't assume that maybe it'll work :-).
— 🍌 John 🍌 (@JohnMu) September 4, 2018
John did also say recently on Reddit "while Googlebot generally doesn't keep cookies, it may sometimes use them." This is in reference to customizing content seen on a page based on cookies.
Forum discussion at Twitter & Reddit.
Note: This story was pre-written and scheduled to be posted now, I am currently offline for a holiday.