Removing/Customizing Done Button from Onboarding

I’ve used Localization to remove the Cancel button completely.

However, when I use the same trick for the Onboarding Vew, I fail to achieve the same result:

1. Is there anything I can do to remove the button completely?

2. To what extent can I use the expression (flask) to customize the Done button visibility?

3. Can the Done button trigger a behavior? Ideally, I want to generate a record (new row) in the User table.