The (identical?) trick doesn't work in cljs, but select-keys does

src/clj/com/rpl/specter/transient.cljx

@@ -50,6 +50,7 @@
   "Navigates to the last element of a transient vector."
   (i/->PosNavigator t-get-last t-update-last))
 
+#+clj
 (defn- select-keys-from-transient-map
   "Selects keys from transient map, because built-in select-keys uses
   `find` which is unsupported."
@@ -66,6 +67,12 @@
                  result)
                (rest m-keys))))))
 
+#+cljs
+(defn- select-keys-from-transient-map
+  "Uses select-keys on a transient map."
+  [m m-keys]
+  (select-keys m m-keys))
+
 (defnav
   ^{:doc "Navigates to the specified persistent submap of a transient map."}
   submap!

test/com/rpl/specter/core_test.cljx

@@ -1054,7 +1054,7 @@
 
 (defspec transient-map-test
   (for-all+
-    [m (gen/not-empty (gen/map gen/keyword gen/int))
+    [m (limit-size 5 (gen/not-empty (gen/map gen/keyword gen/int)))
      new-key gen/keyword]
     (let [existing-key (first (keys m))]
       (every? identity