Adding new AudioProcessorParameter to plugin


I’m experimenting with plugin parameters for my Juce based VST3 plugin that is designed to run in Ableton Live.

If I added a new plugin parameter with a unique id, projects that were created using the previous version of my plugin do not show the new plugin parameters. If I instantiate a plugin in the same project, the new parameters are shown.

From my experience, this worked in Pro Tools with AAX plugins. To confirm this, I created an AAX version of the plugin and did the same test (one version of the plugin with 1 parameter, create a session, the open the same session with an updated version of the plugin with 2 parameters) and Pro Tools shows me the two parameters.

Are there known limitations in Ableton Live about adding new plugin parameters?

I’ve attached a screenshot of my Ableton Live project showing two instances of my plugin. The first one shows a single parameter called Gain 1. The second one shows two plugin parameters Gain 1 and Gain 2. I built the plugin with a single parameter and created the project. I then rebuilt the plugin adding the extra parameter and opened the project. The first instance only shows the original Gain1 parameter. When I added another instance, it showed both Gain 1 and Gain 2.