I have been using Firefox with Ublock Origin as my main browser for a long while. Usually when I get a privacy prompt, I reject cookies, or maybe some sites that are more difficult take me a to a panel that wants me to switch off loads of individual trackers.
How does Ublock handle the cookies? Obviously some are required for site functionality, such as being logged in here, but if I accept cookies (or can’t reject them) then presumably they are still accepted? Or does it accept the essential ones and delete third-party trackers?
uBlock is a content filter. Cookies are set when a server responds to a web (http/https) request. So if uBlock has a domain blocked, not only are any cookies blocked, but no requests make it to that domain (whatever.com) at all.
If a domain is not blocked by uBlock Origin’s filters, then cookies are set per your browser’s configuration. Firefox I believe blocks some 3rd party tracking cookies by default, but can be configured to block all third-party cookies as well, but this may break site functionality like single sign-on.