I'm a long time - many years - LOYAL user of Cookie. It's always worked beautifully.
I upgraded to Sierra v10.12.6 - Safari 12.0.3 Within a few days, all of my cookies vanished. I thought the problem might be the old version of Cookie.
So I upgraded to the trial version of Cookie5 and disabled Cookie 4.6. And reinstated all of my favorites. Like the earlier version of Cookie, I set the timer to delete trackers every two minutes.
I can't tell if the problem is Cookie or Safari.
My banking sites often can't recognize my device. So I have to go through a somewhat tedious process of re-registering my device, getting a code to log in etc.. Same with Twitter. I'm logged out of Twitter daily after literally never being logged out for ten years. Facebook frequently asks me to reinstate my account. (This in spite of fact that I always click "remember me.")
I'm also seeing the following message when I hover the cursor over my favorites: "“domain is a favorite but there are no cookies in browser."
Sometimes I think the issue might be when I delete history - or maybe it's cache. : (
I also checked System Preferences under security/privacy to make sure the "log out after __ of activity" box is unchecked.
Any feedback on this issue is welcome. I love Cookie and want it to work.