use libadwaita HeaderBar

src/app/browser/header.rs

@@ -6,8 +6,8 @@ use subject::Subject;
 use tray::Tray;
 use widget::Widget;
 
-use gtk::{gio::SimpleAction, glib::GString, HeaderBar};
-
+use adw::HeaderBar;
+use gtk::{gio::SimpleAction, glib::GString};
 use std::sync::Arc;
 
 pub struct Header {

src/app/browser/header/widget.rs

@@ -1,4 +1,5 @@
-use gtk::{Box, HeaderBar};
+use adw::HeaderBar;
+use gtk::Box;
 
 pub struct Widget {
     gobject: HeaderBar,

src/app/browser/widget.rs

@@ -2,7 +2,8 @@ mod database;
 
 use database::Database;
 
-use gtk::{prelude::GtkWindowExt, ApplicationWindow, Box, HeaderBar};
+use adw::HeaderBar;
+use gtk::{prelude::GtkWindowExt, ApplicationWindow, Box};
 use sqlite::Transaction;
 
 // Default options