is there a way to prevent users (and in a public category even anonymous users) to expand hidden posts by clicking on the “view hidden post”?
AI-generated summary
The discussion revolves around preventing users from expanding hidden posts in a public category. GuidoD initiated the conversation, seeking a solution to restrict users from viewing hidden posts by clicking on the “view hidden post” link. ondrej suggested changing the delete removed posts after setting to 0, but GuidoD clarified that the posts are not deleted but rather hidden due to flagging. ondrej then proposed hiding the content via CSS or deleting it immediately, but GuidoD emphasized the need to keep the content hidden until the user corrects the post. smrtey pointed out the challenge of allowing users to correct their posts if they are not visible. A potential solution was proposed by smrtey using CSS to hide the “view 1 hidden reply” link. Additionally, ondrej mentioned that users cannot see hidden posts by default unless they are part of a specific group listed in the hidden post visible groups site setting.
Just change this setting to 0 so they delete immediately
delete removed posts after
no these are not deleted posts, just hidden posts due to flagging (automatically hidden due to several flags or hidden due to accepted flags by the moderators).
So changing this setting would not help. 
I know… Once they are hidden if you set that setting to 0 then the hidden content will automatically be deleted so nobody can view it. Or hide via css?
well but the content should not be deleted, it should just kept hidden until the user corrects the post.
Well perhaps via css, I will check that later.
But perhaps someone does already know a solution.
Is there a way for the user to correct the post if it’s not visible? If you want to make the view 1 hidden reply link not visible, that line is <div class="gap">view 1 hidden reply</div> so you can just .gap {display: none}. Not sure what else the gap class covers that you’ll also end up hiding though
I believe that by default, users cannot see hidden posts unless that are part of a group listed in hidden post visible groups site setting. Staff can always view hidden posts.