diff --git a/frontend/util/api.ts b/frontend/util/api.ts
index 1ef958f..733a728 100644
--- a/frontend/util/api.ts
+++ b/frontend/util/api.ts
@@ -67,7 +67,7 @@ export async function fetchJson(
   }
 }
 
-export function makeThumbnailURLSet(
+function legacyMakeThumbnailURLSet(
   thumbnailServerURL: string,
   id: string,
   {
@@ -94,7 +94,7 @@ export function makeThumbnailURLSet(
         : hourglassImage,
     }), {});
 }
-deprecate(makeThumbnailURLSet, 'makeThumbnailURLSet() is deprecated.');
+export const makeThumbnailURLSet = deprecate(legacyMakeThumbnailURLSet, 'makeThumbnailURLSet() is deprecated.');
 
 async function getDirect(relativeURL: string) {
   return fetchJson(`${apiDirectURL}/${relativeURL}`);