How to make a BUI extension run with command/button?

Summary:

Hello, I want to make that an extension for the BUI runs when clicking a button/command.

This because, I've tried to add an "Agent Browser UI Extension" button from the workspace, but is not being showed in the browser interface.

Content (required):

I created a simple extension for BUI that opens a new incident workspace and changes the subject value.

This extension is working fine as a Console Extension (when the user logins into the BUI), however, I need this extension to be triggered when a button/command on a workspace is clicked.

I've tried to add it into the worskpace, as a "Agent Browser UI Extension" button/command, using the Worskpace editor, but when loading into the browser is not showing.