diff --git a/apps/client-standalone/src/local-bridge.ts b/apps/client-standalone/src/local-bridge.ts
index dbd7e326d2..df57db2e84 100644
--- a/apps/client-standalone/src/local-bridge.ts
+++ b/apps/client-standalone/src/local-bridge.ts
@@ -6,10 +6,28 @@ function showFatalErrorDialog(message: string) {
     alert(message);
 }
 
+/**
+ * Collects query params from both `location.search` and the hash's "?..."
+ * suffix. The SPA uses hash-based routing, so flags like `?integrationTest=memory`
+ * often end up after the `#` (e.g. `/#root/foo?integrationTest=memory`) and
+ * are invisible to `location.search`.
+ */
+function collectQueryString(): string {
+    const params = new URLSearchParams(location.search);
+    const hashQueryIndex = location.hash.indexOf("?");
+    if (hashQueryIndex >= 0) {
+        const hashParams = new URLSearchParams(location.hash.substring(hashQueryIndex + 1));
+        for (const [key, value] of hashParams) {
+            if (!params.has(key)) params.set(key, value);
+        }
+    }
+    return params.toString();
+}
+
 export function startLocalServerWorker() {
     if (localWorker) return localWorker;
     localWorker = new LocalServerWorker();
-    localWorker.postMessage({ type: "INIT", queryString: location.search });
+    localWorker.postMessage({ type: "INIT", queryString: collectQueryString() });
 
     // Handle worker errors during initialization
     localWorker.onerror = (event) => {
diff --git a/apps/client-standalone/src/local-server-worker.ts b/apps/client-standalone/src/local-server-worker.ts
index 647db5384b..5ea83dcbec 100644
--- a/apps/client-standalone/src/local-server-worker.ts
+++ b/apps/client-standalone/src/local-server-worker.ts
@@ -74,6 +74,30 @@ let initPromise: Promise<void> | null = null;
 let initError: Error | null = null;
 let queryString = "";
 
+/**
+ * Remove every entry from the OPFS root. Used by integration tests to
+ * guarantee a clean slate — the previous run's DB, logs, and backups would
+ * otherwise survive and cross-contaminate the next run.
+ */
+async function clearOpfs(): Promise<void> {
+    if (typeof navigator === "undefined" || !navigator.storage?.getDirectory) {
+        return;
+    }
+    console.log("[Worker] Clearing OPFS...");
+    const root = await navigator.storage.getDirectory();
+    const names: string[] = [];
+    for await (const name of (root as unknown as { keys(): AsyncIterableIterator<string> }).keys()) {
+        names.push(name);
+    }
+    for (const name of names) {
+        try {
+            await root.removeEntry(name, { recursive: true });
+        } catch (err) {
+            console.warn(`[Worker] Failed to remove OPFS entry "${name}":`, err);
+        }
+    }
+}
+
 /**
  * Load all required modules using dynamic imports.
  * This allows errors to be caught by our error handlers.
@@ -149,7 +173,13 @@ async function initialize(): Promise<void> {
             const params = new URLSearchParams(queryString);
             const integrationTestMode = params.get("integrationTest");
 
+            console.log("Starting with integration test mode ", integrationTestMode);
+
             if (integrationTestMode === "memory") {
+                // Wipe OPFS so e2e runs start from a clean slate (stale DB, logs,
+                // backups from previous sessions would otherwise leak across runs).
+                await clearOpfs();
+
                 // Load the pre-built test fixture database for e2e tests
                 console.log("[Worker] Integration test mode: loading fixture database...");
                 const response = await fetch("/test-fixtures/document.db");
diff --git a/apps/client-standalone/vite.config.mts b/apps/client-standalone/vite.config.mts
index c53855e2ed..af90d334a8 100644
--- a/apps/client-standalone/vite.config.mts
+++ b/apps/client-standalone/vite.config.mts
@@ -164,6 +164,7 @@ if (process.env.TRILIUM_INTEGRATION_TEST) {
                 {
                     src: "../../../packages/trilium-core/src/test/fixtures/document.db",
                     dest: "test-fixtures",
+                    rename: "document.db"
                 }
             ]
         })