Can I customize the Nira toolbar or other interface buttons?

Yes, this is possible as part of the iframe viewer API. You need to create one or more custom pages on your own website, dashboard, blog, etc., and embed a Nira viewer using an <iframe> tag. Additionally, you will need to use basic JavaScript and CSS to customize the experience. Here is a basic example of a custom toolbar page: https://embed-example.nira.app/custom-toolbuttons

You can examine the HTML of this page to understand how your custom toolbar can be implemented.