diff --git a/client/src/services/auth.ts b/client/src/services/auth.ts
index 8624ab4..883b7c2 100644
--- a/client/src/services/auth.ts
+++ b/client/src/services/auth.ts
@@ -45,7 +45,7 @@ export function setActiveMasterKey(key: ArrayBuffer | null) {
 }
 
 // Convert string salt to 32-byte Uint8Array
-const PRF_SALT = new TextEncoder().encode("KapteinsDaagboxPRFSaltForE2EKey")
+const PRF_SALT = new TextEncoder().encode("KapteinsDaagboxPRFSaltForE2EKey_")
 
 export interface RegistrationResult {
   verified: boolean
@@ -88,7 +88,11 @@ export async function registerUser(username: string): Promise<RegistrationResult
   let encryptedMasterKeyPrfIv = null
   let encryptedMasterKeyPrfTag = null
 
-  const prfResults = (credentialResponse as any).clientExtensionResults?.prf
+  console.log('Registration credential response:', credentialResponse)
+  const clientExtensionResults = credentialResponse.clientExtensionResults || {}
+  console.log('Registration client extension results:', clientExtensionResults)
+  const prfResults = (clientExtensionResults as any).prf
+  console.log('Registration PRF extension result:', prfResults)
 
   if (prfResults?.enabled && prfResults.results?.first) {
     const prfKey = await deriveKeyFromPrf(prfResults.results.first)
@@ -152,13 +156,16 @@ export interface LoginResult {
 }
 
 export async function loginUser(username?: string): Promise<LoginResult> {
-  // Log browser supported extensions to diagnose PRF availability
-  console.log(
-    'Browser supported WebAuthn extensions:',
-    window.PublicKeyCredential && (window.PublicKeyCredential as any).getClientExtensionResults
-      ? (window.PublicKeyCredential as any).getClientExtensionResults()
-      : 'none'
-  )
+  // Log browser WebAuthn capabilities to diagnose PRF availability
+  if (window.PublicKeyCredential && (window.PublicKeyCredential as any).getClientCapabilities) {
+    (window.PublicKeyCredential as any).getClientCapabilities().then((caps: any) => {
+      console.log('Browser WebAuthn client capabilities:', caps)
+    }).catch((err: any) => {
+      console.warn('Error reading WebAuthn client capabilities:', err)
+    })
+  } else {
+    console.log('window.PublicKeyCredential.getClientCapabilities is not supported.')
+  }
 
   // 1. Get authentication options
   const optionsRes = await fetch(`${API_BASE}/login-options`, {
diff --git a/server/src/routes/logbooks.ts b/server/src/routes/logbooks.ts
index a4c502c..727cb52 100644
--- a/server/src/routes/logbooks.ts
+++ b/server/src/routes/logbooks.ts
@@ -46,7 +46,7 @@ router.get('/', async (req: any, res) => {
 // 2. Create a new logbook
 router.post('/', async (req: any, res) => {
   try {
-    const { id, encryptedTitle } = req.body
+    const { id, encryptedTitle, encryptedKey, iv, tag } = req.body
     if (!encryptedTitle) {
       return res.status(400).json({ error: 'encryptedTitle is required' })
     }
@@ -55,7 +55,10 @@ router.post('/', async (req: any, res) => {
       data: {
         id: id || undefined,
         userId: req.userId,
-        encryptedTitle
+        encryptedTitle,
+        encryptedKey,
+        iv,
+        tag
       }
     })