diff --git a/docs/js/setup.js b/docs/js/setup.js
index b50d80d..3ceda8a 100644
--- a/docs/js/setup.js
+++ b/docs/js/setup.js
@@ -33,7 +33,7 @@ document.addEventListener("alpine:init", async () => {
   let params = new URLSearchParams((location.hash ?? "#").substr(1));
   let len_filter = decodeFilterParams(params.get("len") ?? "");
   let selected_tileset_key = params.get("tiles") ?? tilesets.selected_tileset;
-  if (!(selected_tileset_key in tilesets.tilesets)) {
+  if (!tilesets.tilesets.map(t => t.key).some(t => selected_tileset_key == t)) {
     console.error(
       "The selected tileset " +
         selected_tileset_key +