Check for plugin win before creating

src/plugins/api.c

@@ -302,6 +302,10 @@ api_win_create(
     void(*callback_exec)(PluginWindowCallback *window_callback, const char *tag, const char * const line),
     void(*callback_destroy)(void *callback))
 {
+    if (callbacks_win_exists(plugin_name, tag)) {
+        return;
+    }
+
     PluginWindowCallback *window = malloc(sizeof(PluginWindowCallback));
     window->callback = callback;
     window->callback_exec = callback_exec;

src/plugins/callbacks.c

@@ -206,6 +206,20 @@ callbacks_add_timed(const char *const plugin_name, PluginTimedFunction *timed_fu
     }
 }
 
+gboolean
+callbacks_win_exists(const char *const plugin_name, const char *tag)
+{
+    GHashTable *window_callbacks = g_hash_table_lookup(p_window_callbacks, plugin_name);
+    if (window_callbacks) {
+        PluginWindowCallback *cb = g_hash_table_lookup(window_callbacks, tag);
+        if (cb) {
+            return TRUE;
+        }
+    }
+
+    return FALSE;
+}
+
 void
 callbacks_add_window_handler(const char *const plugin_name, const char *tag, PluginWindowCallback *window_callback)
 {

src/plugins/callbacks.h

@@ -69,6 +69,7 @@ void callbacks_close(void);
 
 void callbacks_add_command(const char *const plugin_name, PluginCommand *command);
 void callbacks_add_timed(const char *const plugin_name, PluginTimedFunction *timed_function);
+gboolean callbacks_win_exists(const char *const plugin_name, const char *tag);
 void callbacks_add_window_handler(const char *const plugin_name, const char *tag, PluginWindowCallback *window_callback);
 void * callbacks_get_window_handler(const char *tag);