diff --git a/build.sh b/build.sh
index 1c50fee..198f028 100755
--- a/build.sh
+++ b/build.sh
@@ -48,6 +48,49 @@ for path in kernel_extension_dir.glob("*.js"):
 if not patched_files:
     raise SystemExit("No Pyodide dynamic import bundle entry was patched")
 PY
-find content/ -type f -exec cat {} \; | sha256sum | cut -d' ' -f1 > content-hash.txt
+python3 - <<'PY'
+import hashlib
+from pathlib import Path
+
+paths = []
+for root in [
+    Path("content"),
+    Path("pyodide-custom-recipes"),
+    Path("repl"),
+    Path("tskit-launcher/src"),
+    Path("tskit-launcher/style"),
+]:
+    if root.exists():
+        paths.extend(path for path in root.rglob("*") if path.is_file())
+
+for path in [
+    Path("build.sh"),
+    Path("build_pyodide_world.sh"),
+    Path("jupyter-lite.json"),
+    Path("requirements.txt"),
+    Path("tskit-launcher/package.json"),
+    Path("tskit-launcher/package-lock.json"),
+    Path("dist/jupyter-lite.json"),
+    Path("dist/static/pyodide/pyodide-lock.json"),
+    Path("dist/static/pyodide/pyodide.asm.mjs"),
+    Path("dist/static/pyodide/pyodide.asm.wasm"),
+    Path("dist/static/pyodide/python_stdlib.zip"),
+]:
+    if path.exists():
+        paths.append(path)
+
+pyodide_dir = Path("dist/static/pyodide")
+if pyodide_dir.exists():
+    paths.extend(pyodide_dir.glob("pyodide*.mjs"))
+
+digest = hashlib.sha256()
+for path in sorted(set(paths)):
+    digest.update(path.as_posix().encode())
+    digest.update(b"\0")
+    digest.update(path.read_bytes())
+    digest.update(b"\0")
+
+Path("content-hash.txt").write_text(digest.hexdigest() + "\n")
+PY
 HASH=$(cat content-hash.txt)
 echo "{\"contentHash\":\"$HASH\",\"lastUpdated\":\"$(date -u +%Y-%m-%dT%H:%M:%SZ)\"}" > dist/lab/content-config.json
diff --git a/content-hash.txt b/content-hash.txt
index 617c1c4..53eee71 100644
--- a/content-hash.txt
+++ b/content-hash.txt
@@ -1 +1 @@
-8c5267c94cf95d2e4d7cb4f23f84b32ced8dfcbad49614942200e9679ddecb78
+5401e341378a031ff0d1bc35f51696710a091d23df4fa6592bb2ed4805641c21
diff --git a/tskit-launcher/src/index.ts b/tskit-launcher/src/index.ts
index 80112ce..ce85df6 100644
--- a/tskit-launcher/src/index.ts
+++ b/tskit-launcher/src/index.ts
@@ -25,7 +25,7 @@ class CustomLauncher extends Widget implements ILauncher {
   private readonly STORAGE_KEY = 'tskit-launcher-content-hash';
   private readonly AUTO_RESET_KEY = 'tskit-launcher-auto-reset-content-hash';
   private readonly UI_STATE_VERSION_KEY = 'tskit-launcher-ui-state-version';
-  private readonly UI_STATE_VERSION = 'pyodide-2026-0';
+  private readonly UI_STATE_VERSION = 'pyodide-2026-0-native-import';
   private readonly CONFIG_URL = './content-config.json';
 
   constructor() {
@@ -204,8 +204,7 @@ class CustomLauncher extends Widget implements ILauncher {
 
     sessionStorage.setItem(this.AUTO_RESET_KEY, resetMarker);
 
-    this.clearJupyterLiteLocalStorage();
-    await this.deleteIndexedDBDatabases(['JupyterLite Storage']);
+    await this.clearJupyterLiteState();
     this.storeCurrentHash();
     localStorage.setItem(this.UI_STATE_VERSION_KEY, this.UI_STATE_VERSION);
     window.location.reload();