diff --git a/src/pyodide/demo-app/tests/missing_files.py b/src/pyodide/demo-app/tests/missing_files.py
new file mode 100644
index 0000000000..e42b552c50
--- /dev/null
+++ b/src/pyodide/demo-app/tests/missing_files.py
@@ -0,0 +1,29 @@
+async def test_pset():
+    import ifcopenshell.api.pset
+    import ifcopenshell.api.material
+    errors = []
+    try:
+        model = ifcopenshell.file()
+
+        steel_material = ifcopenshell.api.material.add_material(model, name="S355 Steel")
+        steel_pset = ifcopenshell.api.pset.add_pset(model,
+            product=steel_material,
+            name="Pset_MaterialSteel")
+
+        ifcopenshell.api.pset.edit_pset(model,
+            pset=steel_pset,
+            properties={
+                "YieldStress": 355*(10**6),  # Pa (355 MPa)
+            })
+    except Exception as e:
+        errors.append(f"API Error: {e}")
+        return errors
+
+async def test_doc():
+    import ifcopenshell.util.doc
+    errors = []
+    try:
+        ifcopenshell.util.doc.get_entity_doc("IFC4", "IfcWall", recursive=True)
+    except Exception as e:
+        errors.append(f"Doc API Error: {e}")
+    return errors
diff --git a/src/pyodide/demo-app/tests/missing_files_issue.html b/src/pyodide/demo-app/tests/missing_files_issue.html
new file mode 100644
index 0000000000..724bfa7185
--- /dev/null
+++ b/src/pyodide/demo-app/tests/missing_files_issue.html
@@ -0,0 +1,61 @@
+<!DOCTYPE html>
+<html>
+
+<head>
+    <meta charset="utf-8" />
+    <title>Missing Files Issue Demo</title>
+</head>
+
+<body>
+    <div id='status'>Loading...</div>
+    <div id='errors'></div>
+    <script type="text/javascript" src="https://cdn.jsdelivr.net/pyodide/v0.28.0a3/full/pyodide.js"></script>
+    <script type="module">
+        async function main() {
+            document.querySelector("#status").innerHTML = "Initializing pyodide";
+            let pyodide = await loadPyodide();
+            document.querySelector("#status").innerHTML = "Loading dependencies";
+            await pyodide.loadPackage("micropip");
+            await pyodide.loadPackage("numpy");
+            await pyodide.loadPackage("shapely");
+            const micropip = pyodide.pyimport("micropip");
+            await micropip.install("typing-extensions");
+            document.querySelector("#status").innerHTML = "Loading IfcOpenShell";
+            await micropip.install("../wheels/ifcopenshell-0.8.3+34a1bc6-cp313-cp313-emscripten_4_0_9_wasm32.whl");
+
+            document.querySelector("#status").innerHTML = "Loading test script";
+
+            // Load the Python test script
+            await pyodide.runPythonAsync(`
+            from pyodide.http import pyfetch
+            response = await pyfetch("./missing_files.py")
+            with open("missing_files.py", "wb") as f:
+                f.write(await response.bytes())
+            `);
+
+            document.querySelector("#status").innerHTML = "Running tests";
+
+            // Run the async test function
+            let psetErrors = await pyodide.runPythonAsync(`
+            from missing_files import test_pset
+            errors = await test_pset()
+            errors
+            `);
+
+            document.querySelector("#status").innerHTML = "Test completed";
+            document.querySelector("#errors").innerHTML = psetErrors.join("<br>");
+            
+            let docErrors = await pyodide.runPythonAsync(`
+            from missing_files import test_doc
+            errors = await test_doc()
+            errors
+            `);
+
+            document.querySelector("#errors").innerHTML += "<br>" + docErrors.join("<br>");
+        }
+
+        main();
+    </script>
+</body>
+
+</html>
