diff --git a/app/src/main/java/eu/faircode/email/AdapterAccount.java b/app/src/main/java/eu/faircode/email/AdapterAccount.java
index 162e7f8724..fd1082d8e2 100644
--- a/app/src/main/java/eu/faircode/email/AdapterAccount.java
+++ b/app/src/main/java/eu/faircode/email/AdapterAccount.java
@@ -89,7 +89,7 @@ public class AdapterAccount extends RecyclerView.Adapter<AdapterAccount.ViewHold
         setHasStableIds(true);
     }
 
-    public void set(List<EntityAccount> accounts) {
+    public void set(@NonNull List<EntityAccount> accounts) {
         Log.i(Helper.TAG, "Set accounts=" + accounts.size());
 
         final Collator collator = Collator.getInstance(Locale.getDefault());
diff --git a/app/src/main/java/eu/faircode/email/AdapterAttachment.java b/app/src/main/java/eu/faircode/email/AdapterAttachment.java
index bbda80caa6..be3a5b5d29 100644
--- a/app/src/main/java/eu/faircode/email/AdapterAttachment.java
+++ b/app/src/main/java/eu/faircode/email/AdapterAttachment.java
@@ -164,7 +164,7 @@ public class AdapterAttachment extends RecyclerView.Adapter<AdapterAttachment.Vi
         setHasStableIds(true);
     }
 
-    public void set(List<TupleAttachment> attachments) {
+    public void set(@NonNull List<TupleAttachment> attachments) {
         Log.i(Helper.TAG, "Set attachments=" + attachments.size());
 
         Collections.sort(attachments, new Comparator<TupleAttachment>() {
diff --git a/app/src/main/java/eu/faircode/email/AdapterFolder.java b/app/src/main/java/eu/faircode/email/AdapterFolder.java
index 8d2adfa6a8..cee90983ea 100644
--- a/app/src/main/java/eu/faircode/email/AdapterFolder.java
+++ b/app/src/main/java/eu/faircode/email/AdapterFolder.java
@@ -110,7 +110,7 @@ public class AdapterFolder extends RecyclerView.Adapter<AdapterFolder.ViewHolder
         setHasStableIds(true);
     }
 
-    public void set(List<TupleFolderEx> folders) {
+    public void set(@NonNull List<TupleFolderEx> folders) {
         Log.i(Helper.TAG, "Set folders=" + folders.size());
 
         final Collator collator = Collator.getInstance(Locale.getDefault());
diff --git a/app/src/main/java/eu/faircode/email/AdapterIdentity.java b/app/src/main/java/eu/faircode/email/AdapterIdentity.java
index c13dfef92b..fdf84bd5b7 100644
--- a/app/src/main/java/eu/faircode/email/AdapterIdentity.java
+++ b/app/src/main/java/eu/faircode/email/AdapterIdentity.java
@@ -89,7 +89,7 @@ public class AdapterIdentity extends RecyclerView.Adapter<AdapterIdentity.ViewHo
         setHasStableIds(true);
     }
 
-    public void set(List<EntityIdentity> identities) {
+    public void set(@NonNull List<EntityIdentity> identities) {
         Log.i(Helper.TAG, "Set identities=" + identities.size());
 
         final Collator collator = Collator.getInstance(Locale.getDefault());
diff --git a/app/src/main/java/eu/faircode/email/AdapterMessage.java b/app/src/main/java/eu/faircode/email/AdapterMessage.java
index f552578152..58e15e6f53 100644
--- a/app/src/main/java/eu/faircode/email/AdapterMessage.java
+++ b/app/src/main/java/eu/faircode/email/AdapterMessage.java
@@ -120,7 +120,7 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
         setHasStableIds(true);
     }
 
-    public void set(List<TupleMessageEx> messages) {
+    public void set(@NonNull List<TupleMessageEx> messages) {
         Log.i(Helper.TAG, "Set messages=" + messages.size());
 
         Collections.sort(messages, new Comparator<TupleMessageEx>() {
diff --git a/app/src/main/java/eu/faircode/email/FragmentAccount.java b/app/src/main/java/eu/faircode/email/FragmentAccount.java
index 0cdcaf71c1..08bb2771b1 100644
--- a/app/src/main/java/eu/faircode/email/FragmentAccount.java
+++ b/app/src/main/java/eu/faircode/email/FragmentAccount.java
@@ -86,7 +86,7 @@ public class FragmentAccount extends FragmentEx {
 
         // Get arguments
         Bundle args = getArguments();
-        final long id = args.getLong("id", -1);
+        final long id = (args == null ? -1 : args.getLong("id", -1));
 
         // Get providers
         providers = Provider.loadProfiles(getContext());
diff --git a/app/src/main/java/eu/faircode/email/FragmentCompose.java b/app/src/main/java/eu/faircode/email/FragmentCompose.java
index 7c020ff1bf..fef23c88b8 100644
--- a/app/src/main/java/eu/faircode/email/FragmentCompose.java
+++ b/app/src/main/java/eu/faircode/email/FragmentCompose.java
@@ -92,8 +92,8 @@ public class FragmentCompose extends FragmentEx {
 
         // Get arguments
         Bundle args = getArguments();
-        String action = args.getString("action");
-        final long id = (TextUtils.isEmpty(action) ? args.getLong("id") : -1);
+        String action = (args == null ? null : args.getString("action"));
+        final long id = (TextUtils.isEmpty(action) ? (args == null ? -1 : args.getLong("id")) : -1);
 
         // Get controls
         spFrom = view.findViewById(R.id.spFrom);
@@ -242,7 +242,7 @@ public class FragmentCompose extends FragmentEx {
                                 ContactsContract.Contacts.DISPLAY_NAME
                         },
                         null, null, null);
-                if (cursor.moveToFirst()) {
+                if (cursor != null && cursor.moveToFirst()) {
                     int colEmail = cursor.getColumnIndex(ContactsContract.CommonDataKinds.Email.ADDRESS);
                     int colName = cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME);
                     String email = cursor.getString(colEmail);
diff --git a/app/src/main/java/eu/faircode/email/FragmentFolder.java b/app/src/main/java/eu/faircode/email/FragmentFolder.java
index 16b39c057b..33f835c195 100644
--- a/app/src/main/java/eu/faircode/email/FragmentFolder.java
+++ b/app/src/main/java/eu/faircode/email/FragmentFolder.java
@@ -56,7 +56,7 @@ public class FragmentFolder extends FragmentEx {
 
         // Get arguments
         Bundle args = getArguments();
-        final long id = args.getLong("id");
+        final long id = (args == null ? -1 : args.getLong("id"));
 
         // Get controls
         cbSynchronize = view.findViewById(R.id.cbSynchronize);
diff --git a/app/src/main/java/eu/faircode/email/FragmentIdentity.java b/app/src/main/java/eu/faircode/email/FragmentIdentity.java
index a3a538c9cd..ffb96e8c7b 100644
--- a/app/src/main/java/eu/faircode/email/FragmentIdentity.java
+++ b/app/src/main/java/eu/faircode/email/FragmentIdentity.java
@@ -79,7 +79,7 @@ public class FragmentIdentity extends FragmentEx {
 
         // Get arguments
         Bundle args = getArguments();
-        final long id = args.getLong("id", -1);
+        final long id = (args == null ? -1 : args.getLong("id", -1));
 
         // Get providers
         providers = Provider.loadProfiles(getContext());
@@ -221,7 +221,7 @@ public class FragmentIdentity extends FragmentEx {
                 identity.name = Objects.requireNonNull(args.getString("name"));
                 identity.email = Objects.requireNonNull(args.getString("email"));
                 identity.replyto = replyto;
-                identity.host = host;
+                identity.host = Objects.requireNonNull(host);
                 identity.port = Integer.parseInt(port);
                 identity.starttls = starttls;
                 identity.user = Objects.requireNonNull(args.getString("user"));
diff --git a/app/src/main/java/eu/faircode/email/FragmentMessage.java b/app/src/main/java/eu/faircode/email/FragmentMessage.java
index 018fea76ba..35ca62ba76 100644
--- a/app/src/main/java/eu/faircode/email/FragmentMessage.java
+++ b/app/src/main/java/eu/faircode/email/FragmentMessage.java
@@ -92,7 +92,8 @@ public class FragmentMessage extends FragmentEx {
         View view = inflater.inflate(R.layout.fragment_message, container, false);
 
         // Get arguments
-        final long id = getArguments().getLong("id");
+        Bundle args = getArguments();
+        final long id = (args == null ? -1 : args.getLong("id"));
 
         // Get controls
         tvFrom = view.findViewById(R.id.tvFrom);
@@ -467,14 +468,6 @@ public class FragmentMessage extends FragmentEx {
                 .putExtra("action", "reply"));
     }
 
-    private static class MetaData {
-        Throwable ex;
-        EntityFolder folder;
-        boolean hasTrash;
-        boolean hasJunk;
-        boolean hasArchive;
-    }
-
     private static class MoveLoader extends AsyncTaskLoader<List<EntityFolder>> {
         private Bundle args;
 
@@ -493,7 +486,7 @@ public class FragmentMessage extends FragmentEx {
             List<EntityFolder> folders = db.folder().getUserFolders(message.account);
 
             for (int i = 0; i < folders.size(); i++)
-                if (folders.get(i).id == message.folder) {
+                if (folders.get(i).id.equals(message.folder)) {
                     folders.remove(i);
                     break;
                 }
@@ -509,7 +502,7 @@ public class FragmentMessage extends FragmentEx {
             });
 
             EntityFolder inbox = db.folder().getFolderByType(message.account, EntityFolder.TYPE_INBOX);
-            if (message.folder != inbox.id)
+            if (!message.folder.equals(inbox.id))
                 folders.add(0, inbox);
 
             return folders;
diff --git a/app/src/main/java/eu/faircode/email/FragmentMessages.java b/app/src/main/java/eu/faircode/email/FragmentMessages.java
index 44b6d750d8..dc11e0b9cf 100644
--- a/app/src/main/java/eu/faircode/email/FragmentMessages.java
+++ b/app/src/main/java/eu/faircode/email/FragmentMessages.java
@@ -126,7 +126,7 @@ public class FragmentMessages extends FragmentEx {
             pbWait.setVisibility(View.GONE);
             grpReady.setVisibility(View.VISIBLE);
 
-            if (messages == null || messages.size() == 0) {
+            if (messages.size() == 0) {
                 tvNoEmail.setVisibility(View.VISIBLE);
                 rvMessage.setVisibility(View.GONE);
             } else {
diff --git a/app/src/main/java/eu/faircode/email/FragmentWebView.java b/app/src/main/java/eu/faircode/email/FragmentWebView.java
index 5af8173e2b..7ddb2da356 100644
--- a/app/src/main/java/eu/faircode/email/FragmentWebView.java
+++ b/app/src/main/java/eu/faircode/email/FragmentWebView.java
@@ -69,7 +69,8 @@ public class FragmentWebView extends FragmentEx {
             }
         });
 
-        url = getArguments().getString("link");
+        Bundle args = getArguments();
+        url = (args == null ? null : args.getString("link"));
         webview.loadUrl(url);
         setSubtitle(url);