The biggest new feature in Ardour 6.4 is support for plugins in Steinberg’s VST3 plugin format. Yes, that’s right, you can now use VST3 plugins in Ardour, and they work on all platforms, including GNU/Linux, macOS, and Windows. To use them, go to Preferences Plugins and click the “Scan Now” button, which will automatically discover all the VST3 plugins you might have installed in your system. If you don’t have them installed in the standard location, you can specify the folder where they’re installed.