A: Hey there,

I see that Flatsome is a premium theme, so I can't do a quick test. But, I can say that Microthemer works with any theme. Putting aside random compatibility issues that can occur between any two software applications, Microthemer is designed to be completely flexible when it comes to styling WordPress content.

You just load any page inside it and start editing. Microthemer only looks at the final page content (HTML), which is typically produced using a combination of the theme, Gutenberg or page builders, and 3rd party plugins like WooCommerce or contact forms etc. It doesn't need to have any awareness of precisely which tools contributed to the the final page content. And that's what makes it a universal style editor for WordPress.

I hope that helps. Please let me know if you have any more questions.

Thanks!
Sebastian