Added hint

app/src/main/res/layout/fragment_options_send.xml

@@ -141,6 +141,18 @@
             app:layout_constraintTop_toBottomOf="@id/swPlainOnly"
             app:switchPadding="12dp" />
 
+        <TextView
+            android:id="@+id/tvUsenetSignatureHint"
+            android:layout_width="0dp"
+            android:layout_height="wrap_content"
+            android:layout_marginEnd="48dp"
+            android:text="@string/title_advanced_usenet_hint"
+            android:textAppearance="@style/TextAppearance.AppCompat.Small"
+            android:textStyle="italic"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/swUsenetSignature" />
+
         <androidx.appcompat.widget.SwitchCompat
             android:id="@+id/swResizeImages"
             android:layout_width="0dp"
@@ -150,7 +162,7 @@
             android:text="@string/title_advanced_resize_images"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintStart_toStartOf="parent"
-            app:layout_constraintTop_toBottomOf="@id/swUsenetSignature"
+            app:layout_constraintTop_toBottomOf="@id/tvUsenetSignatureHint"
             app:switchPadding="12dp" />
 
         <androidx.appcompat.widget.SwitchCompat

app/src/main/res/values/strings.xml

@@ -409,6 +409,7 @@
     <string name="title_advanced_sync_delay_hint">This will slow down synchronizing messages</string>
 
     <string name="title_advanced_suggest_local_hint">In addition to contacts provided by Android. Contact data will be stored for newly sent or received messages only when enabled.</string>
+    <string name="title_advanced_usenet_hint">Insert \'-- \' between the text and the signature</string>
     <string name="title_advanced_lookup_mx_hint">This will check if DNS MX records exist</string>
     <string name="title_advanced_check_reply_hint">This will check if domain name of the sender and reply addresses are the same</string>