Added compose color hint text

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

@@ -422,6 +422,19 @@
                     app:layout_constraintStart_toStartOf="parent"
                     app:layout_constraintTop_toBottomOf="@id/tvCaptionMessage" />
 
+                <TextView
+                    android:id="@+id/tvComposeColorHint"
+                    android:layout_width="0dp"
+                    android:layout_height="wrap_content"
+                    android:layout_marginTop="6dp"
+                    android:layout_marginEnd="48dp"
+                    android:text="@string/title_advanced_compose_color_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/btnComposeColor" />
+
                 <TextView
                     android:id="@+id/tvComposeFont"
                     android:layout_width="0dp"
@@ -433,7 +446,7 @@
                     android:textColor="?android:attr/textColorPrimary"
                     app:layout_constraintEnd_toEndOf="parent"
                     app:layout_constraintStart_toStartOf="parent"
-                    app:layout_constraintTop_toBottomOf="@id/btnComposeColor" />
+                    app:layout_constraintTop_toBottomOf="@id/tvComposeColorHint" />
 
                 <Spinner
                     android:id="@+id/spComposeFont"

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

@@ -908,6 +908,7 @@
     <string name="title_advanced_auto_identity_hint">This will select the last identity used when selecting a recipient for new messages</string>
     <string name="title_advanced_send_reminders_hint">Show a warning when the message text or the subject is empty or when an attachment might be missing</string>
     <string name="title_advanced_reply_move_hint">The email server could still add the messages to the sent message folder</string>
+    <string name="title_advanced_compose_color_hint">Very light or very dark colors will result in illegible messages on the recipients\' side</string>
     <string name="title_advanced_usenet_hint">Insert \'-- \' between the text and the signature</string>
     <string name="title_advanced_remove_signature_hint">This can result in too little or too much text being removed</string>