The article mentions this: "session cookies that allowed access to Netflix and YouTube (and attached Gmail accounts)"
If you use Gmail it's worth knowing how to log a device off from a different device because it's likely that one day you'll have a device stop working or get lost while it was logged on: Google Account -> Manage your Google Account -> Security -> Your devices -> Manage devices -> ... -> Sign out
If you use Gmail it's worth knowing how to log a device off from a different device because it's likely that one day you'll have a device stop working or get lost while it was logged on: Google Account -> Manage your Google Account -> Security -> Your devices -> Manage devices -> ... -> Sign out