Deprecated: trim(): Passing null to parameter #1 ($string) of type string

-- url of the page with the problem -- : www.3dcreations.uk
-- HikaShop version -- : 6.4.1 stable
-- Joomla version -- : 5.4.5 stable
-- Browser(s) name and version -- : Edge
-- Error-message(debug-mod must be tuned on) -- : Deprecated: trim(): Passing null to parameter #1 ($string) of type string is deprecated in /home/cp3354256/public_html/libraries/src/Document/HtmlDocument.php on line 480

Hello,

I am trying (unsuccessfully) to update my site from Joomla 5.4.5 to 6.1.0. There is an issue with the plugin for backward compatibility which causes the frontend and dashboard to crash. However, in my vain attempt to solve the issues with files and plugins that may cause the update to work, I have slightly broken my pictures page - 3dcreations.uk/index.php/fluid-art/fluid-art-paintings .

Here are the lines from 480 in my php file:

480 $this->_custom[] = trim($html);

return $this;
}

/**
* Returns whether the document is set up to be output as HTML5
*
* @return boolean true when HTML5 is used
*
* @since 3.0.0
*/
In the meantime is it worth reinstalling Hikashop and will it retain all of my data?

Many thanks.

Simon

Solved!

I had left 'debug system' on in order to try and resolve my Joomla upgrade issue.

Thanks.

Simon

Thanks Nicolas!