Omnibear

Repost, like, or reply to anything online. Omnibear is an integrated Micropub client built into your browser. Pop open the menu to post a Note to your blog no matter where you are on the web. Reply to the current page, or right-click any h-entry to interact with it; interacting with posts on twitter.com and facebook.com is also supported.

Your blog must support Web sign-in and micropub. Read more at https://omnibear.com/getting-started