Fix Language Change And Name Collision In Presets

UI/Window/RenderConfigWindow.cs

@@ -1023,12 +1023,16 @@ internal static class RenderConfigWindow
         bool isCurrentPreset = !string.IsNullOrEmpty(_lastLoadedPresetName) &&
                                string.Equals(_lastLoadedPresetName, name, StringComparison.OrdinalIgnoreCase);
 
-        var existing = PresetManager.GetPresets().FirstOrDefault(p => string.Equals(p.Name, name, StringComparison.OrdinalIgnoreCase));
+        // A preset with another name can share the file of this name (PresetManager.GetSafeFileName), e.g. "a/b" and "a_b".
+        var fileName = PresetManager.GetSafeFileName(name);
+        var existing = PresetManager.GetPresets().FirstOrDefault(p =>
+            string.Equals(p.Name, name, StringComparison.OrdinalIgnoreCase) ||
+            string.Equals(PresetManager.GetSafeFileName(p.Name), fileName, StringComparison.OrdinalIgnoreCase));
         if (existing != null && !isCurrentPreset)
         {
             CommonWarningDialogUI.ShowDialog(
                 LocalizationManager.Get("ui.render_config.preset_overwrite_title"),
-                LocalizationManager.Get("ui.render_config.preset_overwrite_desc", name),
+                LocalizationManager.Get("ui.render_config.preset_overwrite_desc", existing.Name),
                 new DialogButton(
                     LocalizationManager.Get("ui.render_config.confirm"),
                     () => DoSavePreset(name, config)
@@ -1190,12 +1194,28 @@ internal static class RenderConfigWindow
     {
         if (_configWindow == null) return;
 
-        if (_presetDropdown != null)
+        if (_presetDropdown == null) return;
+
+        // The preset names are not localized, the Custom label is. The list is rebuilt from the preset names
+        // (which drops the Custom label of the previous language), then the label is decided from the values:
+        // the Custom label of the new language only when the values differ from the last loaded preset.
+        var names = PresetManager.GetPresets().Select(p => p.Name).ToList();
+        if (names.Count == 0)
         {
-            var cur = _presetDropdown.Value;
-            var isCustom = cur == "(Modified)" || cur == "(수정됨)" || cur == CustomPresetLabel;
-            ReloadPresetDropdown(isCustom ? CustomPresetLabel : cur);
+            _presetDropdown.SetValues(new List<string> { CustomPresetLabel });
+            _presetDropdown.Set(CustomPresetLabel, false);
+            UpdateDeleteButtonState();
+            return;
         }
+
+        _presetDropdown.SetValues(names);
+        var loadedName = _lastLoadedPresetName;
+        if (!string.IsNullOrEmpty(loadedName) && names.Contains(loadedName))
+        {
+            _presetDropdown.Set(loadedName, false);
+        }
+
+        UpdatePresetLabel(UiConfig);
     }
 
     private static string GetVersionText()