diff --git a/gtk/gtkalertdialog.c b/gtk/gtkalertdialog.c
index 33ccac37d9..efb4ed4a64 100644
--- a/gtk/gtkalertdialog.c
+++ b/gtk/gtkalertdialog.c
@@ -747,6 +747,9 @@ gtk_alert_dialog_choose_finish (GtkAlertDialog  *self,
   g_return_val_if_fail (g_task_is_valid (result, self), -1);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_alert_dialog_choose, -1);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return (int) g_task_propagate_int (G_TASK (result), error);
 }
 
diff --git a/gtk/gtkcolordialog.c b/gtk/gtkcolordialog.c
index d93c68ad3f..a6e69be7e9 100644
--- a/gtk/gtkcolordialog.c
+++ b/gtk/gtkcolordialog.c
@@ -492,6 +492,9 @@ gtk_color_dialog_choose_rgba_finish (GtkColorDialog  *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_color_dialog_choose_rgba, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return g_task_propagate_pointer (G_TASK (result), error);
 }
 
diff --git a/gtk/gtkfiledialog.c b/gtk/gtkfiledialog.c
index 898650bf9d..590b032779 100644
--- a/gtk/gtkfiledialog.c
+++ b/gtk/gtkfiledialog.c
@@ -976,6 +976,9 @@ gtk_file_dialog_open_finish (GtkFileDialog   *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_file_dialog_open, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return finish_file_op (self, G_TASK (result), error);
 }
 
@@ -1050,6 +1053,9 @@ gtk_file_dialog_select_folder_finish (GtkFileDialog  *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_file_dialog_select_folder, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return finish_file_op (self, G_TASK (result), error);
 }
 
@@ -1120,6 +1126,9 @@ gtk_file_dialog_save_finish (GtkFileDialog   *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_file_dialog_save, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return finish_file_op (self, G_TASK (result), error);
 }
 
@@ -1194,6 +1203,9 @@ gtk_file_dialog_open_multiple_finish (GtkFileDialog   *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_file_dialog_open_multiple, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return finish_multiple_files_op (self, G_TASK (result), error);
 }
 
@@ -1268,6 +1280,9 @@ gtk_file_dialog_select_multiple_folders_finish (GtkFileDialog   *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_file_dialog_select_multiple_folders, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return finish_multiple_files_op (self, G_TASK (result), error);
 }
 
diff --git a/gtk/gtkfontdialog.c b/gtk/gtkfontdialog.c
index 878456d94d..c533dac2cc 100644
--- a/gtk/gtkfontdialog.c
+++ b/gtk/gtkfontdialog.c
@@ -697,6 +697,9 @@ gtk_font_dialog_choose_family_finish (GtkFontDialog  *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_font_dialog_choose_family, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return g_task_propagate_pointer (G_TASK (result), error);
 }
 
@@ -777,6 +780,9 @@ gtk_font_dialog_choose_face_finish (GtkFontDialog  *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_font_dialog_choose_face, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return g_task_propagate_pointer (G_TASK (result), error);
 }
 
@@ -855,6 +861,9 @@ gtk_font_dialog_choose_font_finish (GtkFontDialog  *self,
   g_return_val_if_fail (g_task_is_valid (result, self), NULL);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_font_dialog_choose_font, NULL);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
+
   return g_task_propagate_pointer (G_TASK (result), error);
 }
 
@@ -944,6 +953,8 @@ gtk_font_dialog_choose_font_and_features_finish (GtkFontDialog         *self,
   g_return_val_if_fail (g_task_is_valid (result, self), FALSE);
   g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_font_dialog_choose_font_and_features, FALSE);
 
+  /* Destroy the dialog window not to be bound to GTask lifecycle */
+  g_task_set_task_data (G_TASK (result), NULL, NULL);
   font_result = g_task_propagate_pointer (G_TASK (result), error);
 
   if (font_result)