hubzilla_ynh/sources/doc/acl_dialog_post.html

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     file is for items of that nature. Files and photos etc should use a different help file. -->

<h2>Post Permissions</h2>

<p>The permissions dialog lets you select which channels and/or privacy groups can see the post. You can also select who is explicitly denied access. For example, say you are planning a surprise party for a friend. You can send an invitation post to everyone in your <b>Friends</b> group <i>except</i> the friend you are surprising. In this case you "Show" the <b>Friends</b> group but "Don't show" that one person.</p>

<dl class="text-info dl-terms-large dl-horizontal">
<dt style="width: 3em;">Tip!</td>
<dd style="margin-left: 4em;">The border color of each channel indicates whether that channel &mdash; or one of the groups it's a member of &mdash; will have access to the post. The border color will also indicate when a channel, or group it belongs to, has been explicitly set to "Don't show".</dd>
</dl>

<h3>Why can't I edit a post's permissions after I saved it?</h3>

<p>You are able to change permissons to your files, photos and the likes, but not to posts after you have saved them. The main reason is: Once you have saved a post it is being distributed either to the public channel and from there to other Hubzilla servers or to those you intended it to go. Just like you cannot reclaim something you gave to another person, you cannot change permissions to Hubzilla posts. We would need to track everywhere your posting goes, keep track of everyone you allowed to see it and then keep track of from whom to delete it.</p>
<p>If a posting is public this is even harder, as the Hubzilla is a global network and there is no way to follow a post, let alone reclaim it reliably. Other networks that may receive your post have no reliable way to delete or reclaim the post.</p>