diff --git a/gtk/Dialogs.cc b/gtk/Dialogs.cc
index 927f00d6b..a33c7add8 100644
--- a/gtk/Dialogs.cc
+++ b/gtk/Dialogs.cc
@@ -101,10 +101,10 @@ void gtr_confirm_remove(
     auto d = std::make_shared<Gtk::MessageDialog>(
         parent,
         gtr_sprintf("<big><b>%s</b></big>", primary_text),
-        true,
+        true /*use_markup*/,
         Gtk::MESSAGE_QUESTION,
         Gtk::BUTTONS_NONE,
-        false);
+        true /*modal*/);
 
     if (!secondary_text.empty())
     {
diff --git a/gtk/Utils.cc b/gtk/Utils.cc
index af67e74f9..68ac97164 100644
--- a/gtk/Utils.cc
+++ b/gtk/Utils.cc
@@ -516,9 +516,10 @@ void gtr_unrecognized_url_dialog(Gtk::Widget& parent, Glib::ustring const& url)
     auto w = std::make_shared<Gtk::MessageDialog>(
         *window,
         _("Unrecognized URL"),
-        false,
+        false /*use markup*/,
         Gtk::MESSAGE_ERROR,
-        Gtk::BUTTONS_CLOSE);
+        Gtk::BUTTONS_CLOSE,
+        true /*modal*/);
 
     gstr += gtr_sprintf(_("Transmission doesn't know how to use \"%s\""), url);