diff --git a/app/src/main/java/eu/faircode/email/EmailService.java b/app/src/main/java/eu/faircode/email/EmailService.java
index 8da540b4dc..53f2580999 100644
--- a/app/src/main/java/eu/faircode/email/EmailService.java
+++ b/app/src/main/java/eu/faircode/email/EmailService.java
@@ -29,7 +29,6 @@ import org.bouncycastle.asn1.DEROctetString;
 import org.bouncycastle.asn1.x509.Extension;
 import org.bouncycastle.asn1.x509.GeneralName;
 import org.bouncycastle.asn1.x509.SubjectKeyIdentifier;
-import org.jetbrains.annotations.NotNull;
 
 import java.io.IOException;
 import java.net.Inet4Address;
@@ -1062,7 +1061,7 @@ public class EmailService implements AutoCloseable {
             return fingerprint;
         }
 
-        @NotNull
+        @NonNull
         @Override
         public synchronized String toString() {
             return getCause().toString();
diff --git a/app/src/main/java/eu/faircode/email/Helper.java b/app/src/main/java/eu/faircode/email/Helper.java
index 74430094b8..7e653fd707 100644
--- a/app/src/main/java/eu/faircode/email/Helper.java
+++ b/app/src/main/java/eu/faircode/email/Helper.java
@@ -92,7 +92,6 @@ import androidx.recyclerview.widget.RecyclerView;
 
 import com.google.android.material.bottomnavigation.BottomNavigationView;
 
-import org.jetbrains.annotations.NotNull;
 import org.openintents.openpgp.util.OpenPgpApi;
 
 import java.io.ByteArrayOutputStream;
@@ -301,7 +300,7 @@ public class Helper {
         }
 
         @Override
-        public T get(long timeout, @NotNull TimeUnit unit) throws ExecutionException, InterruptedException, TimeoutException {
+        public T get(long timeout, @NonNull TimeUnit unit) throws ExecutionException, InterruptedException, TimeoutException {
             return wrapped.get(timeout, unit);
         }
     }
diff --git a/app/src/main/java/eu/faircode/email/HtmlHelper.java b/app/src/main/java/eu/faircode/email/HtmlHelper.java
index 347b53a536..8cf947f25e 100644
--- a/app/src/main/java/eu/faircode/email/HtmlHelper.java
+++ b/app/src/main/java/eu/faircode/email/HtmlHelper.java
@@ -1630,6 +1630,7 @@ public class HtmlHelper {
         return preview + "…";
     }
 
+    @NonNull
     static String getText(Context context, String html) {
         final StringBuilder sb = new StringBuilder();
 
diff --git a/app/src/main/java/eu/faircode/email/Shortcuts.java b/app/src/main/java/eu/faircode/email/Shortcuts.java
index 0249f07ba7..4f74d1316f 100644
--- a/app/src/main/java/eu/faircode/email/Shortcuts.java
+++ b/app/src/main/java/eu/faircode/email/Shortcuts.java
@@ -36,6 +36,7 @@ import android.provider.ContactsContract;
 import android.text.TextUtils;
 import android.widget.Toast;
 
+import androidx.annotation.NonNull;
 import androidx.core.app.Person;
 import androidx.core.content.pm.ShortcutInfoCompat;
 import androidx.core.content.pm.ShortcutManagerCompat;
@@ -43,8 +44,6 @@ import androidx.core.graphics.drawable.IconCompat;
 import androidx.lifecycle.LifecycleOwner;
 import androidx.preference.PreferenceManager;
 
-import org.jetbrains.annotations.NotNull;
-
 import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -118,7 +117,7 @@ class Shortcuts {
         }.execute(context, owner, new Bundle(), "shortcuts:update");
     }
 
-    @NotNull
+    @NonNull
     static ShortcutInfoCompat.Builder getShortcut(Context context, InternetAddress address) {
         String name = address.getPersonal();
         String email = address.getAddress();
@@ -154,17 +153,17 @@ class Shortcuts {
         return getShortcut(context, email, name, lookupUri);
     }
 
-    @NotNull
+    @NonNull
     static ShortcutInfoCompat.Builder getShortcut(Context context, EntityContact contact) {
         return getShortcut(context, contact.email, contact.name, contact.avatar);
     }
 
-    @NotNull
+    @NonNull
     private static ShortcutInfoCompat.Builder getShortcut(Context context, String email, String name, String avatar) {
         return getShortcut(context, email, name, avatar == null ? null : Uri.parse(avatar));
     }
 
-    @NotNull
+    @NonNull
     private static ShortcutInfoCompat.Builder getShortcut(Context context, String email, String name, Uri avatar) {
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
         boolean identicons = prefs.getBoolean("identicons", false);