Small layout improvement

app/src/main/java/eu/faircode/email/AdapterMessage.java

@@ -306,12 +306,16 @@ public class AdapterMessage extends RecyclerView.Adapter<AdapterMessage.ViewHold
                 });
             } else
                 itemView.setOnClickListener(this);
+
             ivSnoozed.setOnClickListener(this);
             ivFlagged.setOnClickListener(this);
+
             ivExpanderAddress.setOnClickListener(this);
             ivAddContact.setOnClickListener(this);
+
             btnDownloadAttachments.setOnClickListener(this);
             btnSaveAttachments.setOnClickListener(this);
+
             btnHtml.setOnClickListener(this);
             ibQuotes.setOnClickListener(this);
             ibImages.setOnClickListener(this);

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

@@ -286,6 +286,7 @@
             android:layout_height="24dp"
             android:layout_marginStart="6dp"
             android:layout_marginEnd="6dp"
+            android:background="?android:attr/selectableItemBackground"
             android:src="@drawable/baseline_expand_less_24"
             android:visibility="visible"
             app:layout_constraintEnd_toEndOf="parent"

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

@@ -278,6 +278,7 @@
             android:layout_height="24dp"
             android:layout_marginStart="6dp"
             android:layout_marginEnd="6dp"
+            android:background="?android:attr/selectableItemBackground"
             android:src="@drawable/baseline_expand_less_24"
             android:visibility="visible"
             app:layout_constraintEnd_toEndOf="parent"