Hi @appraiser6524,
Thank you for using Visualizer, and I’m sorry to hear about the difficulties you encountered.
Does the issue occur only when the Visualizer plugin is active, or Visualizer can’t be updated when this line is added to the wp-config.php file?
Currently, we are not aware of such a compatibility issue with Visualizer. You can also check that the code shared doesn’t use stylized quotes when adding it to the config file. You can copy-paste the following snippet.
define( 'FS_METHOD', 'ssh2' );
In case the problem persists after that, you can make sure the ssh2 PHP extension is available on the server where your website is hosted. Your hosting provider can help to check this if needed.
I hope this will help.