diff --git a/Code/Lib/Activity.php b/Code/Lib/Activity.php
index 06559b061..f0953dd26 100644
--- a/Code/Lib/Activity.php
+++ b/Code/Lib/Activity.php
@@ -453,10 +453,6 @@ class Activity
                         $ret[] = ['ttype' => TERM_HASHTAG, 'url' => $t['href'], 'term' => escape_tags((str_starts_with($t['name'], '#')) ? substr($t['name'], 1) : $t['name'])];
                         break;
 
-                    case 'topicalCollection':
-                        $ret[] = ['ttype' => TERM_PCATEGORY, 'url' => $t['href'], 'term' => escape_tags($t['name'])];
-                        break;
-
                     case 'Category':
                         $ret[] = ['ttype' => TERM_CATEGORY, 'url' => $t['href'], 'term' => escape_tags($t['name'])];
                         break;
@@ -505,12 +501,6 @@ class Activity
                         }
                         break;
 
-                    case TERM_PCATEGORY:
-                        if ($t['url'] && $t['term']) {
-                            $ret[] = ['type' => 'topicalCollection', 'href' => $t['url'], 'name' => $t['term']];
-                        }
-                        break;
-
                     case TERM_CATEGORY:
                         if ($t['url'] && $t['term']) {
                             $ret[] = ['type' => 'Category', 'href' => $t['url'], 'name' => $t['term']];
@@ -801,8 +791,10 @@ class Activity
             }
         }
 
-        if ($item['mid'] !== $item['parent_mid']) {
-
+        if ($item['mid'] === $item['parent_mid']) {
+            $activity['isContainedConversation'] = true;
+        }
+        else {
             // inReplyTo needs to be set in the activity for followup actions (Like, Dislike, Announce, etc.),
             // but *not* for comments and RSVPs, where it should only be present in the object
 
@@ -827,11 +819,12 @@ class Activity
                 $cnv = $item['parent_mid'];
             }
         }
-        if (isset($cnv) && $cnv) {
+        if (!empty($cnv)) {
             if (is_string($cnv) && str_starts_with($cnv, z_root())) {
                 $cnv = str_replace(['/item/', '/activity/'], ['/conversation/', '/conversation/'], $cnv);
             }
             $activity['context'] = $cnv;
+            $activity['conversation'] = $cnv;
         }
 
         if (intval($item['item_private']) === 2) {
@@ -1174,6 +1167,7 @@ class Activity
         $activity['attributedTo'] = self::encode_person($item['author'],false);
 
         if ($item['mid'] === $item['parent_mid']) {
+            $activity['isContainedConversation'] = true;
             if (in_array($activity['commentPolicy'], ['public', 'authenticated'])) {
                 $activity['canReply'] = ACTIVITY_PUBLIC_INBOX;
             } elseif (in_array($activity['commentPolicy'], ['contacts', 'specific'])) {
@@ -1199,11 +1193,12 @@ class Activity
                 $cnv = $item['parent_mid'];
             }
         }
-        if (isset($cnv) && $cnv) {
+        if (!empty($cnv)) {
             if (is_string($cnv) && str_starts_with($cnv, z_root())) {
                 $cnv = str_replace(['/item/', '/activity/'], ['/conversation/', '/conversation/'], $cnv);
             }
             $activity['context'] = $cnv;
+            $activity['conversation'] = $cnv;
         }
 
         // provide ocap access token for private media.
@@ -4573,17 +4568,8 @@ class Activity
             'oauthRegistrationEndpoint' => 'litepub:oauthRegistrationEndpoint',
             'sensitive' => 'as:sensitive',
             'movedTo' => 'as:movedTo',
-            'copiedTo' => 'as:copiedTo',
             'alsoKnownAs' => 'as:alsoKnownAs',
             'EmojiReact' => 'as:EmojiReact',
-            'commentPolicy' => 'nomad:commentPolicy',
-            'topicalCollection' => 'nomad:topicalCollection',
-            'eventRepeat' => 'nomad:eventRepeat',
-            'emojiReaction' => 'nomad:emojiReaction',
-            'expires' => 'nomad:expires',
-            'directMessage' => 'nomad:directMessage',
-            'Category' => 'nomad:Category',
-            'replyTo' => 'nomad:replyTo',
             'PropertyValue' => 'schema:PropertyValue',
             'value' => 'schema:value',
             'discoverable' => 'toot:discoverable',
@@ -4594,6 +4580,16 @@ class Activity
             'canReply' => 'toot:canReply',
             'approval' => 'toot:approval',
             'Identity' => 'fep:Identity',
+            'isContainedConversation' => 'nomad:isContainedConversation',
+            'conversation' => 'nomad:conversation',
+            'commentPolicy' => 'nomad:commentPolicy',
+            'eventRepeat' => 'nomad:eventRepeat',
+            'emojiReaction' => 'nomad:emojiReaction',
+            'expires' => 'nomad:expires',
+            'directMessage' => 'nomad:directMessage',
+            'Category' => 'nomad:Category',
+            'replyTo' => 'nomad:replyTo',
+            'copiedTo' => 'as:copiedTo',
         ];
     }
 
diff --git a/Code/Module/Search.php b/Code/Module/Search.php
index bc76b0dac..acced3b60 100644
--- a/Code/Module/Search.php
+++ b/Code/Module/Search.php
@@ -53,11 +53,13 @@ class Search extends Controller
         }
         Navbar::set_selected('Search');
 
-        $format = (($_REQUEST['module_format']) ? $_REQUEST['module_format'] : '');
+        $format = (($_REQUEST['module_format']) ?: '');
+        if (ActivityStreams::is_as_request()) {
+            $format = 'json';
+        }
         if ($format !== '') {
             $this->updating = $this->loading = 1;
         }
-
         $observer = App::get_observer();
         $observer_hash = (($observer) ? $observer['xchan_hash'] : '');
 
diff --git a/FEDERATION.md b/FEDERATION.md
index e5833dd12..e171b9a4e 100644
--- a/FEDERATION.md
+++ b/FEDERATION.md
@@ -19,7 +19,7 @@ The URL endpoints are:
     
 Direct Messages
 
-Direct Messages (DM) are differentiated from other private messaging using the zot:directMessage flag (boolean). This is compatible with the same facility provided by other projects in other namespaces and is not prefixed within activities so that these may potentially be aggregated.
+Direct Messages (DM) are differentiated from other private messaging using the nomad:directMessage flag (boolean). This is compatible with the same facility provided by other projects in other namespaces and is not prefixed within activities so that these may potentially be aggregated.
 
 Events