Back in October, we explained how to mark themes as favorites in the WordPress theme directory. Although users could install their favorite plugins in WordPress 4.3, they couldn’t install their favorite themes.
I created a Trac ticket asking the WordPress development team to consider adding the ability to install themes marked as favorites. Thanks to the volunteer efforts of contributors, users can install their favorite themes in WordPress 4.4.
To see your favorite themes, browse to the Appearance > Themes section of the WordPress backend and click the Add New link. Then click on the Favorites tab. You may be prompted to login to WordPress.org as favorites are tied to the WordPress.org username.
You can also browse a different user’s favorite themes by entering their WordPress.org username into the box.
Once you find the theme you want, click the Install button. Keep in mind that you can only favorite a theme from its detailed information page on the WordPress theme directory and not from the backend of WordPress. Also note that like plugins, themes marked as favorites will show up on your WordPress.org user profile.