Fatal error created by plugin

I’ve been getting reports from my WordPress installation of a fatal error being created by the PHP Compatibility checker. Here’s the reported error information:

Error Details
=============
An error of type E_ERROR was caused in line 89 of the file /home/ms101admin/public_html/wp-content/plugins/php-compatibility-checker/vendor/phpcompatibility/php-compatibility/PHPCompatibility/Sniffs/Operators/ChangedConcatOperatorPrecedenceSniff.php. Error message: Uncaught Error: Call to undefined method PHPCompatibility\Sniffs\Operators\ChangedConcatOperatorPrecedenceSniff::isUnaryPlusMinus() in /home/ms101admin/public_html/wp-content/plugins/php-compatibility-checker/vendor/phpcompatibility/php-compatibility/PHPCompatibility/Sniffs/Operators/ChangedConcatOperatorPrecedenceSniff.php:89
Stack trace:
#0 /home/ms101admin/public_html/wp-content/plugins/php-compatibility-checker/vendor/squizlabs/php_codesniffer/CodeSniffer/File.php(576): PHPCompatibility\Sniffs\Operators\ChangedConcatOperatorPrecedenceSniff->process(Object(PHP_CodeSniffer_File), 202)
#1 /home/ms101admin/public_html/wp-content/plugins/php-compatibility-checker/vendor/squizlabs/php_codesniffer/CodeSniffer.php(1894): PHP_CodeSniffer_File->start(NULL)
#2 /home/ms101admin/public_html/wp-content/plugins/php-compatibility-checker/vendor/squizlabs/php_codesniffer/CodeSniffer.php(1772): PHP_CodeSniffer->_processFile(‘/home/ms101admi…’, NULL)
#3 /home/ms101admin/public_html/wp-content/plugins/php-compatibility-che

I’ve deactivated the plugin for the moment.

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