Third Party Cookies not being removed

Running the latest version or e-Privacy Directive 3.10.13 on a Joomla 3.8.12 site.

The session cookie for the domain is being removed. However third party cookies (YouTube, Vimeo, Issuu and others) are not being removed when required.

I have tried adding the (dot) domain and '/' to Global Configuration > Cookie Settings with no success.

I have added all the third party cookie domains to the advanced tab of the plugin with no success.

What I need to query is whether the ACL steps of the configuration instructions (i.e creating a new user group and a new viewing access level) are NECESSARY for this plugin to successfully remove third party cookies? I have no modules or plugins that I want to block before cookies are accepted but do I still need to do the ACL steps to make third party cookie removal work?

If I DO need to do it is it necessary to set viewing access levels for both 'Cookies accepted' and 'Cookies not accepted'?

Thanks

I have tried the ACL steps and kept them simple and in line with the instructions I hope! Attaching some screenshots of our user groups and levels setup and the plugin advanced config. Have I made a simple mistake somewhere?

3rd party cookies can be prevented, but once set they cannot be removed by any site but the site that set them.

So, my extension uses the Joomla ACL to prevent elements that set 3rd party cookies from loading. Once they're loaded, however, your site/browser is restricted by the Javascript Same-Origin policy. google.com can't set cookies for your site, and your site can't set cookies for google.com.

en.wikipedia.org/wiki/Same-origin_policy

Thank you Michael. If my understanding is correct you're saying that a 3rd party cookie from YouTube, Vimeo etc can't be removed if it's already been set. My problem is that they are being set right from the get-go even if the user has requested to decline all cookies. My third party cookies all originate from iframes (e.g. Issuu) or from embeds via the All Videos plugin (e.g. YouTube).

I think I have set everything up right because I can make a module appear and disappear when assigning it to a viewing level. Further the session cookie (?) (the one with the website's URL as its name) comes and goes correctly too. As I say I just need to prevent 3rd party cookies from being set in the first place which should be possible.