It would be nice to support multiple workspace roots rather than assuming that the user has only one project open. For example, here's how the Git view shows multiple folders:

I don't know how widespread this practice is among Nextflow developers, so it's not urgent.
You would likely want to select only those folders that are a Nextflow project (i.e. does it contain a main.nf or nextflow.config in the root directiry?). This would involve replacing the Processes/Workflows view with a single "Projects" view with a dropdown to focus on a specific project.