matrix: Enable MSC4108 to allow Signing in with QR Code

modules/matrix/default.nix

@@ -124,17 +124,9 @@ in
         enable_room_list_search = true;
         encryption_enabled_by_default_for_room_type = "off";
         event_cache_size = "100K";
-
-        # https://github.com/element-hq/synapse/issues/11203
-        # No YAML deep-merge, so this needs to be in secret extraConfigFiles
-        # together with msc3861
-        #experimental_features = {
-        #  # Room summary API
-        #  msc3266_enabled = true;
-        #  # Rendezvous server for QR Code generation
-        #  msc4108_enabled = true;
-        #};
-
+        experimental = {
+          msc4108_enabled = true;
+        };
         federation_rr_transactions_per_room_per_second = 50;
         federation_client_minimum_tls_version = "1.2";
         forget_rooms_on_leave = true;

modules/nginx-matrix/default.nix

@@ -24,6 +24,14 @@ let
       secure_backup_required = false;
       secure_backup_setup_methods = [ ];
     };
+    "m.integrations" = {
+      managers = [
+        {
+          api_url = "https://dimension.${domain}/api/v1/scalar";
+          ui_url = "https://dimension.${domain}/element";
+        }
+      ];
+    };
   };
   wellKnownServer = domain: { "m.server" = "matrix.${domain}:8448"; };
   wellKnownSupport = {