I used to struggle to access certain websites that insisted on enabling third party cookies as well as first party if they were going to let me in. Some of these are everyday sites. (off hand I don't remember which ones), But now, since I installed this extension it goes like this: if they are worth visiting occasionally I grey list em. If they are frequent sites I visit several times a day I white list em, so I don't have to keep logging in every time. Then, I go in and wipe out all cookies from the days browsing activities in the evening, or twice a day if I have been on many seldom sites that I won't visit again that day.
It's really getting to utilize this according to your habits. If a website is that stubborn, like a site I stumble on from time to time-Washingtontimes.com which won't let you go far if you have an adblocker. Well, I won't let any site bypass my security so, I go elsewhere.That's my rule of thumb.