It does what it's supposed to, but I have multiple Google accounts, and it seems to only want to have me logged into one in the little pop-up, and if I log in to a different one it just opens a new tab with that account without changing the main one, which is a bit annoying.

Update 19/08/21: Just gives Google 403 error whenever it's opened. Completely unusable in its current state and I'm forced to open Google Keep normally, defeating the purpose entirely.