Post info is not displayed in author archives

[webkompaan]

The Post Info is missing on the author pages, even with all plugins disabled and only with the Genesis and Breakthrough theme enabled. Both are up to date. The below code in the functions file of the theme should display the post info, but it only shows 'by' and 'on', while on other pages the post info is displayed correctly.

function breakthrough_modify_post_info( $post_info ) {

	global $post;

	setup_postdata( $post );
	$post_avatar = get_avatar( get_the_author_meta( 'email' ), 36 );

	if ( is_single() ) {
		$post_info = $post_avatar . '<i class="byline">by</i> [post_author_posts_link] <i>on</i> [post_date after=""]  [post_comments] [post_edit]';
	} else {
		$post_info = '<i class="byline">by</i> [post_author_posts_link] <i>on</i> [post_date]  [post_comments] [post_edit]';
	}

	return $post_info;

}

https://www.devrijdenkers.nl/author/oliver/

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