author.php

<?php
defined('JPATH_BASE') or die;

// Import the Profile Picture library
jimport('profilepicture.profilepicture');

// Get the current user object
$user = JFactory::getUser();

// Instantiate the ProfilePicture class with User ID
$profilepicture = new ProfilePicture($user->get('id'));
$profilepicture = $profilepicture->toHTML(PROFILEPICTURE_SIZE_200, $displayData['item']->author, ['class' => 'thumbnail col-md-10 img-responsive']);

?>
<dd class="createdby" itemprop="author" itemscope itemtype="https://schema.org/Person">
	<?php $author 		= ($displayData['item']->created_by_alias ? $displayData['item']->created_by_alias : $displayData['item']->author); ?>
	<?php $author 		= '<div itemprop="name" class="authorname col-md-24">' . $author . '</div>'; ?>
	<?php $kontakt 		= '<div itemprop="name" class="authorcontact col-md-24">' . JText::_('TPL_DATAGON_AUTHOR_CONTACT') . '</div>'; ?>
	<?php $authorinfo 	= '<div class="authorinfo col-md-14">' . $author . $kontakt . '</div>'; ?>
	
	<?php if (!empty($displayData['item']->contact_link ) && $displayData['params']->get('link_author') == true) : ?>
		<?php echo JHtml::_('link', $displayData['item']->contact_link, $profilepicture . $authorinfo, array('itemprop' => 'image', 'itemprop' => 'url', 'class' => 'authorbox' )); ?>
	<?php else :?>
		<?php echo $author; ?>
	<?php endif; ?>
</dd>

Hi,
Can you try this please ::
1-
REPLACE :
$profilepicture = new ProfilePicture($user->get('id'));
WITH:
$profilepicture = new ProfilePicture($this->escape($item->created_by));
IF NOT WORK , CHECK WITH THIS :
$profilepicture = new ProfilePicture($item->created_by);

IF NOT WORK BOTH PLEASE PROVIDE ME THE WHOLE PHP CODE OF FILE OR WHICH IS LOCATE EXACTLY FOLDER IN JOOMLA

Best Regards,
Mierza

Good evening,
thanks for your reply!
Sorry but nothing of this worked for me.
The original code is located in this folder: https://github.com/joomla/joomla-cms/blob/staging/layouts/joomla/content/info_block/author.php

Kind Regards,
Jan

Hi,
I used the following line of code and it works for me:

$profilepicture = new ProfilePicture($displayData['item']->created_by); //passes in the author ID

instead of:

$profilepicture = new ProfilePicture($user->get('id')); // this will pass in the currently logged in user ID

Note:
In the author.php file above the following two lines should be removed:

//Get the current user object
$user = JFactory::getUser();

Regards,
Darran