diff --git a/js/examples/leaflet.html b/js/examples/leaflet.html
index 09015d9..7be4ca0 100644
--- a/js/examples/leaflet.html
+++ b/js/examples/leaflet.html
@@ -15,17 +15,16 @@
     <body>
         <div id="map"></div>
         <script type="text/javascript">
-            const map = L.map("map").setView([0, 0], 0);
+            const map = L.map("map");
 
             const p = new pmtiles.PMTiles(
-              "https://pmtiles.io/stamen_toner(raster)CC-BY+ODbL_z3.pmtiles"
+              "https://air.mtn.tw/flowers.pmtiles"
             );
             p.getHeader().then((h) => {
               let layer = pmtiles.leafletRasterLayer(p, {
-                maxzoom: h.maxZoom,
-                attribution:
-                  'Map tiles by <a href="http://stamen.com">Stamen Design</a>, under <a href="http://creativecommons.org/licenses/by/3.0">CC BY 3.0</a>. Data by <a href="http://openstreetmap.org">OpenStreetMap</a>, under <a href="http://www.openstreetmap.org/copyright">ODbL</a>.',
+                maxNativeZoom: h.maxZoom
               });
+              map.fitBounds(L.latLngBounds([h.minLat, h.minLon],[h.maxLat, h.maxLon]));
               layer.addTo(map);
             });
         </script>
diff --git a/js/src/adapters.ts b/js/src/adapters.ts
index e1cd829..b0e67f0 100644
--- a/js/src/adapters.ts
+++ b/js/src/adapters.ts
@@ -77,6 +77,7 @@ export const leafletRasterLayer = (source: PMTiles, options: unknown) => {
       }
 
       if (tile.el.cancel) tile.el.cancel();
+      if (tile.el.src) window.URL.revokeObjectURL(tile.el.src);
 
       tile.el.width = 0;
       tile.el.height = 0;
@@ -256,7 +257,6 @@ export class Protocol {
     const x = result[3];
     const y = result[4];
 
-    const header = await instance.getHeader();
     const resp = await instance?.getZxy(+z, +x, +y, abortController.signal);
     abortController.signal.throwIfAborted();
     if (resp) {
@@ -266,6 +266,7 @@ export class Protocol {
         expires: resp.expires,
       };
     }
+    const header = await instance.getHeader();
     if (header.tileType === TileType.Mvt) {
       if (this.errorOnMissingTile) {
         throw new Error("Tile not found.");
diff --git a/js/src/index.ts b/js/src/index.ts
index 4981b52..7a2121b 100644
--- a/js/src/index.ts
+++ b/js/src/index.ts
@@ -551,23 +551,6 @@ function deserializeIndex(buffer: ArrayBuffer): Entry[] {
   return entries;
 }
 
-function detectVersion(a: ArrayBuffer): number {
-  const v = new DataView(a);
-  if (v.getUint16(2, true) === 2) {
-    console.error(
-      "PMTiles spec version 2 is not supported; please see github.com/protomaps/PMTiles for tools to upgrade"
-    );
-    return 2;
-  }
-  if (v.getUint16(2, true) === 1) {
-    console.error(
-      "PMTiles spec version 1 is not supported; please see github.com/protomaps/PMTiles for tools to upgrade"
-    );
-    return 1;
-  }
-  return 3;
-}
-
 /**
  * Error thrown when a response for PMTiles over HTTP does not match previous, cached parts of the archive.
  * The default PMTiles implementation will catch this error once internally and retry a request.
