Problem/Motivation
Comments currently include a shortcut link which allows privileged users to quickly publish them. This is especially useful if comments are configured to default to unpublished, awaiting the approval of an administrator or site moderator. However, there's no equivalent shortcut to unpublish a comment which would be useful in the opposite case (comments are published by default and spam/inappropriate comments are unpublished by moderators).
This is also an inconsistency which would be a DX improvements: having a path to unpublish comments in tests, adding a views field which provides an unpublish link, etc.
Finally, much of the current administration wording refers to "approving" comments which, in reality, is simply changing the comment's publish status. This wording should be updated on the back end to "publish" which is consistent throughout core and pairs better with "unpublish" vs. "unapprove".
Proposed resolution
Add unpublish equivalents to the current publish functionality.
Remaining tasks
Needs review and change notice.
User interface changes
All administration text referring to "approving" a comment has been changed to "publishing", user-facing text has been left alone as it is still accurate (they are waiting for their comment to be approved). The Comment Approval Queue is now titled the Comment Unpublished Queue and has moved from '/admin/content/comment/approval' to '/admin/content/comment/unpublished'. The path for publishing a comment has moved from '/comment/{comment}/approve' to '/comment/{comment}/publish' and a new path for unpublishing a comment has been added at '/comment/{comment}/unpublish'.
API changes
A new route has been added for unpublishing a comment has been added at '/comment/{comment}/unpublish'. Additionally, the existing route for publishing a comment has had its path changed from '/comment/{comment}/approve' to '/comment/{comment}/publish' for consistency. The entity access operation has changed from 'approve' to 'publish' and the comment administration overview form $type argument now accepts either 'unpublished' or 'new' vs. 'approval' or 'new'.
Original report by droplet
On the frontend it has a way to approve a comment but no way to undo it.
Suggest add AJAX-action to approve & unapproved them
