https://gitlab.gnome.org/GNOME/gnome-commander/-/merge_requests/213

--- gnome-commander-1.18.1/libgcmd/gnome-cmd-plugin.cc.orig
+++ gnome-commander-1.18.1/libgcmd/gnome-cmd-plugin.cc
@@ -25,76 +25,43 @@
 #include "gnome-cmd-state.h"
 #include "gnome-cmd-plugin.h"
 
-G_DEFINE_TYPE (GnomeCmdPlugin, gnome_cmd_plugin, G_TYPE_OBJECT)
 
-/*******************************
- * Gtk class implementation
- *******************************/
-
-static void gnome_cmd_plugin_class_init (GnomeCmdPluginClass *klass)
-{
-    GnomeCmdPluginClass *plugin_class;
-
-    plugin_class = GNOME_CMD_PLUGIN_CLASS (klass);
-
-    plugin_class->create_actions = NULL;
-    plugin_class->create_main_menu = NULL;
-    plugin_class->create_popup_menu_items = NULL;
-    plugin_class->configure = NULL;
-}
-
-
-static void gnome_cmd_plugin_init (GnomeCmdPlugin *plugin)
+void gnome_cmd_plugin_free (GnomeCmdPlugin *plugin)
 {
+    if (plugin->free)
+        plugin->free (plugin);
 }
 
-/***********************************
- * Public functions
- ***********************************/
 
 GSimpleActionGroup *gnome_cmd_plugin_create_actions (GnomeCmdPlugin *plugin, const gchar *name)
 {
-    GnomeCmdPluginClass *klass;
-
-    g_return_val_if_fail (GNOME_CMD_IS_PLUGIN (plugin), NULL);
-
-    klass = GNOME_CMD_PLUGIN_GET_CLASS (plugin);
-
-    return klass->create_actions (plugin, name);
+    if (plugin->create_actions)
+        return plugin->create_actions (plugin, name);
+    else
+        return NULL;
 }
 
 
 GMenuModel *gnome_cmd_plugin_create_main_menu (GnomeCmdPlugin *plugin, GnomeCmdState *state)
 {
-    GnomeCmdPluginClass *klass;
-
-    g_return_val_if_fail (GNOME_CMD_IS_PLUGIN (plugin), NULL);
-
-    klass = GNOME_CMD_PLUGIN_GET_CLASS (plugin);
-
-    return klass->create_main_menu (plugin, state);
+    if (plugin->create_main_menu)
+        return plugin->create_main_menu (plugin, state);
+    else
+        return NULL;
 }
 
 
 GMenuModel *gnome_cmd_plugin_create_popup_menu_items (GnomeCmdPlugin *plugin, GnomeCmdState *state)
 {
-    GnomeCmdPluginClass *klass;
-
-    g_return_val_if_fail (GNOME_CMD_IS_PLUGIN (plugin), NULL);
-
-    klass = GNOME_CMD_PLUGIN_GET_CLASS (plugin);
-
-    return klass->create_popup_menu_items (plugin, state);
+    if (plugin->create_popup_menu_items)
+        return plugin->create_popup_menu_items (plugin, state);
+    else
+        return NULL;
 }
 
 
 void gnome_cmd_plugin_configure (GnomeCmdPlugin *plugin, GtkWindow *parent_window)
 {
-    GnomeCmdPluginClass *klass;
-
-    g_return_if_fail (GNOME_CMD_IS_PLUGIN (plugin));
-
-    klass = GNOME_CMD_PLUGIN_GET_CLASS (plugin);
-
-    klass->configure (plugin, parent_window);
+    if (plugin->configure)
+        plugin->configure (plugin, parent_window);
 }
--- gnome-commander-1.18.1/libgcmd/gnome-cmd-plugin.h.orig
+++ gnome-commander-1.18.1/libgcmd/gnome-cmd-plugin.h
@@ -21,28 +21,13 @@
 
 #pragma once
 
-#define GNOME_CMD_TYPE_PLUGIN              (gnome_cmd_plugin_get_type ())
-#define GNOME_CMD_PLUGIN(obj)              (G_TYPE_CHECK_INSTANCE_CAST((obj), GNOME_CMD_TYPE_PLUGIN, GnomeCmdPlugin))
-#define GNOME_CMD_PLUGIN_CLASS(klass)      (G_TYPE_CHECK_CLASS_CAST((klass), GNOME_CMD_TYPE_PLUGIN, GnomeCmdPluginClass))
-#define GNOME_CMD_IS_PLUGIN(obj)           (G_TYPE_CHECK_INSTANCE_TYPE((obj), GNOME_CMD_TYPE_PLUGIN))
-#define GNOME_CMD_IS_PLUGIN_CLASS(klass)   (G_TYPE_CHECK_CLASS_TYPE ((klass), GNOME_CMD_TYPE_PLUGIN))
-#define GNOME_CMD_PLUGIN_GET_CLASS(obj)    (G_TYPE_INSTANCE_GET_CLASS((obj), GNOME_CMD_TYPE_PLUGIN, GnomeCmdPluginClass))
-
-
 typedef struct _GnomeCmdPlugin GnomeCmdPlugin;
-typedef struct _GnomeCmdPluginClass GnomeCmdPluginClass;
-typedef struct _GnomeCmdPluginPrivate GnomeCmdPluginPrivate;
 
 typedef GnomeCmdPlugin *(*PluginConstructorFunc)(void);
 
 struct _GnomeCmdPlugin
 {
-    GObject parent;
-};
-
-struct _GnomeCmdPluginClass
-{
-    GObjectClass parent_class;
+    void (* free) (GnomeCmdPlugin *plugin);
 
     GSimpleActionGroup *(* create_actions) (GnomeCmdPlugin *plugin, const gchar *name);
 
@@ -52,7 +37,7 @@
 };
 
 
-GType gnome_cmd_plugin_get_type ();
+void gnome_cmd_plugin_free (GnomeCmdPlugin *plugin);
 
 GSimpleActionGroup *gnome_cmd_plugin_create_actions (GnomeCmdPlugin *plugin, const gchar *name);
 
--- gnome-commander-1.18.1/plugins/fileroller/file-roller-plugin.cc.orig
+++ gnome-commander-1.18.1/plugins/fileroller/file-roller-plugin.cc
@@ -163,9 +163,10 @@
  * The File-Roller-Plugin
  ***********************************/
 
-
-struct FileRollerPluginPrivate
+struct FileRollerPlugin
 {
+    GnomeCmdPlugin parent;
+
     gchar *action_group_name;
 
     GtkWidget *conf_dialog;
@@ -179,10 +180,6 @@
     PluginSettings *settings;
 };
 
-
-G_DEFINE_TYPE_WITH_PRIVATE (FileRollerPlugin, file_roller_plugin, GNOME_CMD_TYPE_PLUGIN)
-
-
 gchar *GetGfileAttributeString(GFile *gFile, const char *attribute);
 
 static void run_cmd (const gchar *work_dir, const gchar *cmd)
@@ -356,10 +353,9 @@
     gboolean name_ok = FALSE;
     GList *files;
 
-    FileRollerPlugin *plugin = FILE_ROLLER_PLUGIN (user_data);
-    FileRollerPluginPrivate *priv = (FileRollerPluginPrivate *) file_roller_plugin_get_instance_private (plugin);
+    FileRollerPlugin *plugin = (FileRollerPlugin *) user_data;
 
-    files = priv->state->active_dir_selected_files;
+    files = plugin->state->active_dir_selected_files;
 
     do
     {
@@ -388,7 +384,7 @@
         gtk_widget_show (entry);
         gtk_box_append (GTK_BOX (gtk_dialog_get_content_area (GTK_DIALOG (dialog))), entry);
 
-        gchar *locale_format = g_locale_from_utf8 (priv->file_prefix_pattern, -1, nullptr, nullptr, nullptr);
+        gchar *locale_format = g_locale_from_utf8 (plugin->file_prefix_pattern, -1, nullptr, nullptr, nullptr);
         char s[256];
         time_t t = time (nullptr);
 
@@ -403,7 +399,7 @@
         g_free (locale_format);
         gchar *file_prefix = g_locale_to_utf8 (s, -1, nullptr, nullptr, nullptr);
 
-        gchar *archive_name_tmp = g_strdup_printf("%s%s", file_prefix, priv->default_ext);
+        gchar *archive_name_tmp = g_strdup_printf("%s%s", file_prefix, plugin->default_ext);
         auto file_name_tmp = GetGfileAttributeString(GNOME_CMD_FILE_BASE (files->data)->gFile, G_FILE_ATTRIBUTE_STANDARD_DISPLAY_NAME);
         archive_name = new_string_with_replaced_keyword(archive_name_tmp, "$N", file_name_tmp);
         gtk_editable_set_text (GTK_EDITABLE (entry), archive_name);
@@ -425,7 +421,7 @@
     while (name_ok == FALSE && ret == GTK_RESPONSE_OK);
 
     if (ret == GTK_RESPONSE_OK)
-        do_add_to_archive (name, priv->state);
+        do_add_to_archive (name, plugin->state);
 
     gtk_window_destroy (GTK_WINDOW (dialog));
 }
@@ -433,9 +429,9 @@
 
 static GSimpleActionGroup *create_actions (GnomeCmdPlugin *plugin, const gchar *name)
 {
-    FileRollerPluginPrivate *priv = (FileRollerPluginPrivate *) file_roller_plugin_get_instance_private (FILE_ROLLER_PLUGIN (plugin));
+    FileRollerPlugin *fr = (FileRollerPlugin *) plugin;
 
-    priv->action_group_name = g_strdup (name);
+    fr->action_group_name = g_strdup (name);
 
     GSimpleActionGroup *group = g_simple_action_group_new ();
     static const GActionEntry entries[] = {
@@ -466,7 +462,7 @@
     if (num_files <= 0)
         return nullptr;
 
-    FileRollerPluginPrivate *priv = (FileRollerPluginPrivate *) file_roller_plugin_get_instance_private (FILE_ROLLER_PLUGIN (plugin));
+    FileRollerPlugin *priv = (FileRollerPlugin *) plugin;
 
     priv->state = state;
 
@@ -548,15 +544,13 @@
 
 static void on_configure_close (GtkButton *btn, FileRollerPlugin *plugin)
 {
-    FileRollerPluginPrivate *priv = (FileRollerPluginPrivate *) file_roller_plugin_get_instance_private (plugin);
-
-    priv->default_ext = gtk_combo_box_text_get_active_text (GTK_COMBO_BOX_TEXT (priv->conf_combo));
-    priv->file_prefix_pattern = g_strdup (get_entry_text (priv->conf_entry, "file_prefix_pattern_entry"));
+    plugin->default_ext = gtk_combo_box_text_get_active_text (GTK_COMBO_BOX_TEXT (plugin->conf_combo));
+    plugin->file_prefix_pattern = g_strdup (get_entry_text (plugin->conf_entry, "file_prefix_pattern_entry"));
 
-    g_settings_set_string (priv->settings->file_roller_plugin, GCMD_PLUGINS_FILE_ROLLER_DEFAULT_TYPE, priv->default_ext);
-    g_settings_set_string (priv->settings->file_roller_plugin, GCMD_PLUGINS_FILE_ROLLER_PREFIX_PATTERN, priv->file_prefix_pattern);
+    g_settings_set_string (plugin->settings->file_roller_plugin, GCMD_PLUGINS_FILE_ROLLER_DEFAULT_TYPE, plugin->default_ext);
+    g_settings_set_string (plugin->settings->file_roller_plugin, GCMD_PLUGINS_FILE_ROLLER_PREFIX_PATTERN, plugin->file_prefix_pattern);
 
-    gtk_widget_hide (priv->conf_dialog);
+    gtk_widget_hide (plugin->conf_dialog);
 }
 
 
@@ -600,7 +594,7 @@
     GtkWidget *dialog, *grid, *cat, *label, *vbox, *entry;
     GtkWidget *combo;
 
-    FileRollerPluginPrivate *priv = (FileRollerPluginPrivate *) file_roller_plugin_get_instance_private (FILE_ROLLER_PLUGIN (plugin));
+    FileRollerPlugin *priv = (FileRollerPlugin *) plugin;
 
     dialog = gnome_cmd_dialog_new (parent_window, _("Options"));
     gtk_window_set_modal (GTK_WINDOW (dialog), TRUE);
@@ -681,36 +675,21 @@
  * Gtk class implementation
  *******************************/
 
-static void dispose (GObject *object)
-{
-    FileRollerPlugin *plugin = FILE_ROLLER_PLUGIN (object);
-    FileRollerPluginPrivate *priv = (FileRollerPluginPrivate *) file_roller_plugin_get_instance_private (plugin);
-
-    g_clear_pointer (&priv->default_ext, g_free);
-    g_clear_pointer (&priv->file_prefix_pattern, g_free);
-    g_clear_pointer (&priv->action_group_name, g_free);
-
-    G_OBJECT_CLASS (file_roller_plugin_parent_class)->dispose (object);
-}
-
-
-static void file_roller_plugin_class_init (FileRollerPluginClass *klass)
+static void dispose (GnomeCmdPlugin *plugin)
 {
-    GObjectClass *object_class = G_OBJECT_CLASS (klass);
-    GnomeCmdPluginClass *plugin_class = GNOME_CMD_PLUGIN_CLASS (klass);
+    auto fr = (FileRollerPlugin *) plugin;
 
-    object_class->dispose = dispose;
+    g_clear_pointer (&fr->default_ext, g_free);
+    g_clear_pointer (&fr->file_prefix_pattern, g_free);
+    g_clear_pointer (&fr->action_group_name, g_free);
 
-    plugin_class->create_actions = create_actions;
-    plugin_class->create_main_menu = create_main_menu;
-    plugin_class->create_popup_menu_items = create_popup_menu_items;
-    plugin_class->configure = configure;
+    g_free (plugin);
 }
 
 
 static void file_roller_plugin_init (FileRollerPlugin *plugin)
 {
-    FileRollerPluginPrivate *priv = (FileRollerPluginPrivate *) file_roller_plugin_get_instance_private (plugin);
+    FileRollerPlugin *priv = plugin;
 
     priv->settings = plugin_settings_new();
 
@@ -770,18 +749,27 @@
 }
 
 
-/***********************************
- * Public functions
- ***********************************/
-
-GnomeCmdPlugin *file_roller_plugin_new ()
+static GnomeCmdPlugin *file_roller_plugin_new ()
 {
-    FileRollerPlugin *plugin = (FileRollerPlugin *) g_object_new (file_roller_plugin_get_type (), nullptr);
+    FileRollerPlugin *plugin = g_new0 (FileRollerPlugin, 1);
+
+    plugin->parent.free = dispose;
+
+    plugin->parent.create_actions = create_actions;
+    plugin->parent.create_main_menu = create_main_menu;
+    plugin->parent.create_popup_menu_items = create_popup_menu_items;
+    plugin->parent.configure = configure;
 
-    return GNOME_CMD_PLUGIN (plugin);
+    file_roller_plugin_init (plugin);
+
+    return (GnomeCmdPlugin *) plugin;
 }
 
 
+/***********************************
+ * Public functions
+ ***********************************/
+
 extern "C"
 {
     GnomeCmdPlugin *create_plugin ()
--- gnome-commander-1.18.1/plugins/fileroller/file-roller-plugin.h.orig
+++ gnome-commander-1.18.1/plugins/fileroller/file-roller-plugin.h
@@ -25,30 +25,6 @@
 G_DECLARE_FINAL_TYPE (PluginSettings, plugin_settings, GCMD, SETTINGS, GObject)
 PluginSettings *plugin_settings_new (void);
 
-#define FILE_ROLLER_PLUGIN(obj) \
-    G_TYPE_CHECK_INSTANCE_CAST (obj, file_roller_plugin_get_type (), FileRollerPlugin)
-#define FILE_ROLLER_PLUGIN_CLASS(klass) \
-    G_TYPE_CHECK_CLASS_CAST (klass, file_roller_plugin_get_type (), FileRollerPluginClass)
-#define IS_FILE_ROLLER_PLUGIN(obj) \
-    G_TYPE_CHECK_INSTANCE_TYPE (obj, file_roller_plugin_get_type ())
-
-
-typedef struct _FileRollerPlugin FileRollerPlugin;
-typedef struct _FileRollerPluginClass FileRollerPluginClass;
-
-struct _FileRollerPlugin
-{
-    GnomeCmdPlugin parent;
-};
-
-struct _FileRollerPluginClass
-{
-    GnomeCmdPluginClass parent_class;
-};
-
-GType file_roller_plugin_get_type ();
-
-GnomeCmdPlugin *file_roller_plugin_new ();
 extern "C"
 {
     GnomeCmdPlugin *create_plugin ();
--- gnome-commander-1.18.1/plugins/test/test-plugin.cc.orig
+++ gnome-commander-1.18.1/plugins/test/test-plugin.cc
@@ -42,15 +42,14 @@
     WEBPAGE
 };
 
-struct TestPluginPrivate
+struct TestPlugin
 {
+    GnomeCmdPlugin parent;
+
     gchar *action_group_name;
 };
 
 
-G_DEFINE_TYPE_WITH_PRIVATE(TestPlugin, test_plugin, GNOME_CMD_TYPE_PLUGIN)
-
-
 static void show_dummy_dialog(GtkWindow *parent_window)
 {
     GtkWidget *dialog;
@@ -73,7 +72,7 @@
 
 static GSimpleActionGroup *create_actions (GnomeCmdPlugin *plugin, const gchar *name)
 {
-    TestPluginPrivate *priv = (TestPluginPrivate *) test_plugin_get_instance_private (TEST_PLUGIN (plugin));
+    TestPlugin *priv = (TestPlugin *) plugin;
 
     priv->action_group_name = g_strdup (name);
 
@@ -88,7 +87,7 @@
 
 static GMenuModel *create_main_menu (GnomeCmdPlugin *plugin, GnomeCmdState *state)
 {
-    TestPluginPrivate *priv = (TestPluginPrivate *) test_plugin_get_instance_private (TEST_PLUGIN (plugin));
+    TestPlugin *priv = (TestPlugin *) plugin;
 
     GMenu *menu = g_menu_new ();
     gchar *action_name = g_strdup_printf ("%s.dummy", priv->action_group_name);
@@ -100,7 +99,7 @@
 
 static GMenuModel *create_popup_menu_items (GnomeCmdPlugin *plugin, GnomeCmdState *state)
 {
-    TestPluginPrivate *priv = (TestPluginPrivate *) test_plugin_get_instance_private (TEST_PLUGIN (plugin));
+    TestPlugin *priv = (TestPlugin *) plugin;
 
     GMenu *menu = g_menu_new ();
     gchar *action_name = g_strdup_printf ("%s.dummy", priv->action_group_name);
@@ -116,50 +115,34 @@
 }
 
 
-
-
-/*******************************
- * Gtk class implementation
- *******************************/
-
-static void dispose (GObject *object)
+static void dispose (GnomeCmdPlugin *plugin)
 {
-    TestPluginPrivate *priv = (TestPluginPrivate *) test_plugin_get_instance_private (TEST_PLUGIN (object));
+    TestPlugin *priv = (TestPlugin *) plugin;
 
     g_clear_pointer (&priv->action_group_name, g_free);
 
-    G_OBJECT_CLASS (test_plugin_parent_class)->dispose (object);
+    g_free (plugin);
 }
 
-static void test_plugin_class_init (TestPluginClass *klass)
+
+static GnomeCmdPlugin *test_plugin_new ()
 {
-    G_OBJECT_CLASS (klass)->dispose = dispose;
+    TestPlugin *plugin = g_new0 (TestPlugin, 1);
 
-    GnomeCmdPluginClass *plugin_class = GNOME_CMD_PLUGIN_CLASS (klass);
+    plugin->parent.free = dispose;
+    plugin->parent.create_actions = create_actions;
+    plugin->parent.create_main_menu = create_main_menu;
+    plugin->parent.create_popup_menu_items = create_popup_menu_items;
+    plugin->parent.configure = configure;
 
-    plugin_class->create_actions = create_actions;
-    plugin_class->create_main_menu = create_main_menu;
-    plugin_class->create_popup_menu_items = create_popup_menu_items;
-    plugin_class->configure = configure;
+    return (GnomeCmdPlugin *) plugin;
 }
 
 
-static void test_plugin_init (TestPlugin *plugin)
-{
-}
-
 /***********************************
  * Public functions
  ***********************************/
 
-GnomeCmdPlugin *test_plugin_new ()
-{
-    TestPlugin *plugin = (TestPlugin *) g_object_new (test_plugin_get_type (), NULL);
-
-    return GNOME_CMD_PLUGIN (plugin);
-}
-
-
 extern "C"
 {
     GnomeCmdPlugin *create_plugin ()
--- gnome-commander-1.18.1/plugins/test/test-plugin.h.orig
+++ gnome-commander-1.18.1/plugins/test/test-plugin.h
@@ -21,31 +21,6 @@
 
 #pragma once
 
-#define TEST_PLUGIN(obj) \
-    G_TYPE_CHECK_INSTANCE_CAST (obj, test_plugin_get_type (), TestPlugin)
-#define TEST_PLUGIN_CLASS(klass) \
-    G_TYPE_CHECK_CLASS_CAST (klass, test_plugin_get_type (), TestPluginClass)
-#define IS_TEST_PLUGIN(obj) \
-    G_TYPE_CHECK_INSTANCE_TYPE (obj, test_plugin_get_type ())
-
-
-typedef struct _TestPlugin TestPlugin;
-typedef struct _TestPluginClass TestPluginClass;
-
-struct _TestPlugin
-{
-    GnomeCmdPlugin parent;
-};
-
-struct _TestPluginClass
-{
-    GnomeCmdPluginClass parent_class;
-};
-
-
-GType test_plugin_get_type ();
-
-GnomeCmdPlugin *test_plugin_new ();
 extern "C"
 {
     GnomeCmdPlugin *create_plugin   ();