Headline studio is a brilliant little tool if you write many blog posts, promo emails, or social media posts. Clicking on the extension opens up a sidebar that lets you get ideas and feedback on any headlines, so you can improve them and even get AI rewrites.
The extension performs well overall and even shows up as a little button on subject fields. Sometimes it can be glitchy after you're logged out, but overall 100% recommend.

I just downloaded this plugin for Firefox and I'm loving it. It allows me to access the Headline Studio headline generator and SEO optimizer w/out having to open a new tab and launch the page. Big time saving already!

This extension needs to go back to the drawing board. I could never get the thing to work even after downloading it several times. Don't waste your time.