Fix multiseries cards in embedding (thanks to @alex-mcleod for help)

src/metabase/api/embed.clj

@@ -164,7 +164,11 @@
   [dashboard-id dashcard-id card-id]
   (let [param-id->param (u/key-by :id (db/select-one-field :parameters Dashboard :id dashboard-id))]
     ;; throw a 404 if there's no matching DashboardCard so people can't get info about other Cards that aren't in this Dashboard
-    (for [param-mapping (api/check-404 (db/select-one-field :parameter_mappings DashboardCard :id dashcard-id, :dashboard_id dashboard-id, :card_id card-id))
+    ;; we don't need to check that card-id matches the DashboardCard because we might be trying to get param info for
+    ;; a series belonging to this dashcard (card-id might be for a series)
+    (for [param-mapping (api/check-404 (db/select-one-field :parameter_mappings DashboardCard
+                                         :id           dashcard-id
+                                         :dashboard_id dashboard-id))
           :when         (= (:card_id param-mapping) card-id)
           :let          [param (get param-id->param (:parameter_id param-mapping))]
           :when         param]

test/metabase/api/embed_test.clj

@@ -6,11 +6,14 @@
             [metabase
              [http-client :as http]
              [util :as u]]
-            [metabase.api.public-test :as public-test]
+            [metabase.api
+             [embed :as embed-api]
+             [public-test :as public-test]]
             [metabase.models
              [card :refer [Card]]
              [dashboard :refer [Dashboard]]
-             [dashboard-card :refer [DashboardCard]]]
+             [dashboard-card :refer [DashboardCard]]
+             [dashboard-card-series :refer [DashboardCardSeries]]]
             [metabase.test
              [data :as data]
              [util :as tu]]
@@ -413,10 +416,20 @@
 
 ;;; ------------------------------------------------------------ Other Tests ------------------------------------------------------------
 
-(tu/resolve-private-vars metabase.api.embed
-  remove-locked-and-disabled-params)
-
 ;; parameters that are not in the `embedding-params` map at all should get removed by `remove-locked-and-disabled-params`
 (expect
   {:parameters []}
-  (remove-locked-and-disabled-params {:parameters {:slug "foo"}} {}))
+  (#'embed-api/remove-locked-and-disabled-params {:parameters {:slug "foo"}} {}))
+
+;; make sure that multiline series word as expected (#4768)
+(expect
+  "completed"
+  (with-embedding-enabled-and-new-secret-key
+    (tt/with-temp Card [series-card {:dataset_query {:database (data/id)
+                                                     :type     :query
+                                                     :query    {:source-table (data/id :venues)}}}]
+      (with-temp-dashcard [dashcard {:dash {:enable_embedding true}}]
+        (tt/with-temp DashboardCardSeries [series {:dashboardcard_id (u/get-id dashcard)
+                                                   :card_id          (u/get-id series-card)
+                                                   :position         0}]
+          (:status (http/client :get 200 (str (dashcard-url (assoc dashcard :card_id (u/get-id series-card)))))))))))