Description of the issue:
Clicking on the trash icon does not remove the sites.
I have already tried clearing all browsing data to no effect.
How can this issue be reproduced?
While your individual site settings for it is that Shields is off, then you’d always be allowing cookies. Hence why you can’t manually edit it out without visiting the site and activating Shields again.
if this method work, then easiest way would be to delete “site and shields settings” from privacy and security, clear browsing data → advanced → select all time and check only site and shields settings and click clear data…