diff --git a/app/admin.py b/app/admin.py
index ece448e..c45575f 100644
--- a/app/admin.py
+++ b/app/admin.py
@@ -393,6 +393,9 @@ async def admin_direct_messages(
     db_session: AsyncSession = Depends(get_db_session),
     cursor: str | None = None,
 ) -> templates.TemplateResponse:
+    # The process for building DMs thread is a bit compex in term of query
+    # but it does not require an extra tables to index/manage threads
+
     inbox_convos = (
         (
             await db_session.execute(
@@ -407,6 +410,8 @@ async def admin_direct_messages(
                 .where(
                     models.InboxObject.visibility == ap.VisibilityEnum.DIRECT,
                     models.InboxObject.ap_context.is_not(None),
+                    # Skip transient object like poll relies
+                    models.InboxObject.is_transient.is_(False),
                 )
                 .group_by(models.InboxObject.ap_context, models.InboxObject.actor_id)
             )
@@ -427,6 +432,8 @@ async def admin_direct_messages(
                 .where(
                     models.OutboxObject.visibility == ap.VisibilityEnum.DIRECT,
                     models.OutboxObject.ap_context.is_not(None),
+                    # Skip transient object like poll relies
+                    models.OutboxObject.is_transient.is_(False),
                 )
                 .group_by(models.OutboxObject.ap_context)
             )
@@ -435,6 +442,7 @@ async def admin_direct_messages(
         .all()
     )
 
+    # Build a "threads index" by combining objects from the inbox and outbox
     convos = {}
     for inbox_convo in inbox_convos:
         if inbox_convo.ap_context not in convos:
@@ -467,6 +475,7 @@ async def admin_direct_messages(
                 convos[outbox_convo.ap_context]["most_recent_from_outbox"],
             )
 
+    # Fetch the latest object for each threads
     convos_with_last_from_inbox = []
     convos_with_last_from_outbox = []
     for context, convo in convos.items():
@@ -514,6 +523,8 @@ async def admin_direct_messages(
         .unique()
         .all()
     )
+
+    # Build the template response
     threads = []
     for anybox_object in sorted(
         last_from_inbox + last_from_outbox,
diff --git a/app/boxes.py b/app/boxes.py
index 8f1f0a8..fcbda71 100644
--- a/app/boxes.py
+++ b/app/boxes.py
@@ -154,6 +154,12 @@ async def send_announce(db_session: AsyncSession, ap_object_id: str) -> None:
     if not inbox_object:
         raise ValueError(f"{ap_object_id} not found in the inbox")
 
+    if inbox_object.visibility not in [
+        ap.VisibilityEnum.PUBLIC,
+        ap.VisibilityEnum.UNLISTED,
+    ]:
+        raise ValueError("Cannot announce non-public object")
+
     announce_id = allocate_outbox_id()
     announce = {
         "@context": ap.AS_CTX,
diff --git a/app/main.py b/app/main.py
index 37a3adc..217e611 100644
--- a/app/main.py
+++ b/app/main.py
@@ -76,7 +76,6 @@ _RESIZED_CACHE: MutableMapping[tuple[str, int], tuple[bytes, str, Any]] = LFUCac
 # TODO(ts):
 #
 # Next:
-# - Add a TTL cache for the LD sig (no need to re-compute)
 # - only show 10 most recent threads in DMs
 # - custom CSS for disabled button (e.g. sharing on a direct post)
 # - prevent double accept/double follow
diff --git a/app/templates/utils.html b/app/templates/utils.html
index 7860f50..300c701 100644
--- a/app/templates/utils.html
+++ b/app/templates/utils.html
@@ -105,12 +105,12 @@
 </form>
 {% endmacro %}
 
-{% macro admin_announce_button(ap_object_id, disabled=False, permalink_id=None) %}
+{% macro admin_announce_button(ap_object_id, permalink_id=None) %}
 <form action="{{ request.url_for("admin_actions_announce") }}" method="POST">
     {{ embed_csrf_token() }}
     {{ embed_redirect_url(permalink_id) }}
     <input type="hidden" name="ap_object_id" value="{{ ap_object_id }}">
-    <input type="submit" value="share" {% if disabled %}title="Cannot share non-public content" disabled{% endif %}>
+    <input type="submit" value="share">
 </form>
 {% endmacro %}
 
@@ -574,13 +574,15 @@
                 {% endif %}
             </li>
 
+            {% if object.visibility in [visibility_enum.PUBLIC, visibility_enum.UNLISTED] %}
             <li>
                 {% if object.announced_via_outbox_object_ap_id %}
                     {{ admin_undo_button(object.liked_via_outbox_object_ap_id, "unshare") }}
                 {% else %}
-                    {{ admin_announce_button(object.ap_id, disabled=object.visibility not in [visibility_enum.PUBLIC, visibility_enum.UNLISTED], permalink_id=object.permalink_id) }}
+                    {{ admin_announce_button(object.ap_id, permalink_id=object.permalink_id) }}
                 {% endif %}
             </li>
+            {% endif %}
 
             <li>
                 {{ admin_profile_button(object.actor.ap_id) }}