Customizing Divi Author Pages
The Divi Theme doesn't currently offer much in the way of options for customizing the author post listings pages (the pages that show all the posts by a single author). This post gives some options for styling the author post pages, which will hopefully give you a starting point for customizing these pages.
Creating an author.php Page
When a user visits an author page on your site, they are presented with a list of posts of that author. But where does the layout of that page come from? When the author page is visited Divi looks for a template file to use to display the page. It considers several options, including a file called "author.php" which specifies a template to use for all author pages. If the theme doesn't include this file (which Divi doesn't), WordPress looks for fallback templates. In the case of Divi it ends up using the main Divi index.php file, located in the root of the Divi theme folder.
If we want to edit the authors pages, one option is to make a copy of this index.php file and call it author.php. Putting this in the main Divi directory (the same one as has the index.php file) will cause WordPress to use the author.php copy instead of the index.php file.
We could leave the new author.php file where it is, but unfortunately it would get overwritten next time you update Divi. It is much better to create a child theme and put the author.php file in the main folder of this child theme. Now your changes will survive any Divi updates.
I'm not going to go into a lot of detail of all the things that could be done with this file. But I will give a simple example to give you a taste of what's possible.
In the author.php file you'll see the start of the code looks something like this:
Now we'll change this to add a simple author bio box with the following code:
Save the author.php file.
Note that on earlier versions of WordPress (pre-4.9), you may need to replace "user_description" in the above code with just "description".
Now, with the child theme active, view the author page. You should see something like this author bio box at the top of your author page:
Using the Taxonomy Layout Injector plugin
The Taxonomy Layout Injector plugin allows you to use the Divi Builder to edit archive pages such as the author archive pages.
It lets you assign a Divi Builder layout to use on the author pages. The plugin includes custom modules to display the author's photo and name. I don't currently see any mention in the plugin's docs of a way to display the author bio, but one way to do it would be to add a code module in that layout and within the code module put a shortcode that displays the author description.
The free Author Bio Shortcode plugin adds just such a shortcode. It hasn't been updated in a while, but given that it's dealing with quite basic WordPress functionality it's likely that it still works. There are probably others that do something similar, but that's the first one I saw.
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