Use accelerator for actions instead of key presses.

    <property name="resizable">False</property>

    <property name="window-position">3</property>

    <signal name="destroy" handler="on_window_destroy" swapped="no"/>

    <signal name="key-press-event" handler="on_window_key_press" swapped="no"/>

    <child type="titlebar">

      <object class="GtkHeaderBar" id="header_bar">

        <property name="visible">True</property>

            save_button.sensitive = true;

        }

        /* The on window key press callback. */

        [GtkCallback]

        private bool on_window_key_press(Gdk.EventKey e) {

            return false;

        }

        /**

         * Updates the encoding popover.

         * @param percentage the percentage of the encoding.