What is the issue with Smarty that the user is facing regarding HTML indentation?

The issue the user is facing with Smarty regarding HTML indentation is that the output HTML is not properly indented, making it difficult to read and maintain the code. To solve this issue, the user can enable the auto-indent feature in Smarty by setting the "auto_indent" option to true in the Smarty configuration.

// Enable auto-indent feature in Smarty
$smarty = new Smarty();
$smarty->setAutoIndent(true);