--- a/mod_muc_restrict_media/mod_muc_restrict_media.lua	Wed Nov 24 16:27:20 2021 +0100
+++ b/mod_muc_restrict_media/mod_muc_restrict_media.lua	Wed Nov 24 16:28:35 2021 +0100
@@ -43,6 +43,7 @@
 	local allow_unaffiliated_media = not should_restrict_media(room);
 	table.insert(form, {
 		name = "{xmpp:prosody.im}muc#roomconfig_unaffiliated_media",
+		type = "boolean",
 	});
 	formdata["{xmpp:prosody.im}muc#roomconfig_unaffiliated_media"] = allow_unaffiliated_media;
 end);