Whenever you reply to post update on google+ it could be really good if you can see this option to reply to person who posted the update, as by default there is no such option in google+ updates and posts to reply, the only thing you can do is to reply as a comment to the current update as shown in the image below.
Once you install this extension you will see the option to reply to author with which you can easily and directly reply to the person who posted the update.
When you reply to author, his google+ profile will automatically get mentioned, instead of you requiring it to type which is really useful feature on its own.
It will add the following functions to google+ profile.
- Reply and Reply to Author links for easy +mentions of other users
- Badges the favicon with a number when you have new messages
- Ctrl+Enter and Shift+Enter submit a comment or post
- Header bar floats down as you scroll
- Adds a dropdown next to share with additional sharing options (Twitter/Facebook/Email)
If you encounter any issues in this extension, report issues here and It might ask you for access to a few Google sites (this is required because this modifies content on any page that contains Google+ elements). Make sure you refresh any Google+ windows that you had open before installing.
Download, Install Replies and more for Google+ from here