Diff

--- a/plugins/mod_muc_mam.lua	Mon Mar 04 13:13:37 2019 +0100
+++ b/plugins/mod_muc_mam.lua	Mon Mar 04 13:46:09 2019 +0100
@@ -213,6 +213,7 @@
 		if not is_stanza(item) then
 			item = st.deserialize(item);
 		end
+		item.attr.to = nil;
 		item.attr.xmlns = "jabber:client";
 		fwd_st:add_child(item);
 
@@ -334,6 +335,7 @@
 
 	if stanza.name == "message" and self:get_whois() == "anyone" then
 		stored_stanza = st.clone(stanza);
+		stored_stanza.attr.to = nil;
 		local actor = jid_bare(self._occupants[stanza.attr.from].jid);
 		local affiliation = self:get_affiliation(actor) or "none";
 		local role = self:get_role(actor) or self:get_default_role(affiliation);
@@ -344,12 +346,13 @@
 	-- Policy check
 	if not archiving_enabled(self) then return end -- Don't log
 
-	-- And stash it
+	-- Save the type in the 'with' field, allows storing presence without conflicts
 	local with = stanza.name
 	if stanza.attr.type then
 		with = with .. "<" .. stanza.attr.type
 	end
 
+	-- And stash it
 	local id = archive:append(room_node, nil, stored_stanza, time_now(), with);
 
 	if id then