UnusedIssueHandlerSuppression
Emitted when an issue type suppression in the configuration file is not being used to suppress an issue.
Enabled by findUnusedIssueHandlerSuppression
<?php
$a = 'Hello, World!';
echo $a;
<?xml version="1.0" encoding="UTF-8"?>
<issueHandlers>
<PossiblyNullOperand errorLevel="suppress"/>
</issueHandlers>