I’ve noticed some warnings/errors too. I’m running a checker for PHP7 errors/warnings and have this output upon testing:
FILE: /http/dev.example.com/wp-content/plugins/download-manager/libs/class.Crypt.php
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FOUND 0 ERRORS AND 10 WARNINGS AFFECTING 5 LINES
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19 | WARNING | Extension 'mcrypt' is deprecated since PHP 7.1 - use openssl (preferred) or pecl/mcrypt once available instead.
19 | WARNING | Function mcrypt_get_iv_size() is deprecated since PHP 7.1; use OpenSSL instead
21 | WARNING | Extension 'mcrypt' is deprecated since PHP 7.1 - use openssl (preferred) or pecl/mcrypt once available instead.
21 | WARNING | Function mcrypt_create_iv() is deprecated since PHP 7.1; use OpenSSL instead
23 | WARNING | Extension 'mcrypt' is deprecated since PHP 7.1 - use openssl (preferred) or pecl/mcrypt once available instead.
23 | WARNING | Function mcrypt_encrypt() is deprecated since PHP 7.1; use OpenSSL instead
43 | WARNING | Extension 'mcrypt' is deprecated since PHP 7.1 - use openssl (preferred) or pecl/mcrypt once available instead.
43 | WARNING | Function mcrypt_get_iv_size() is deprecated since PHP 7.1; use OpenSSL instead
53 | WARNING | Extension 'mcrypt' is deprecated since PHP 7.1 - use openssl (preferred) or pecl/mcrypt once available instead.
53 | WARNING | Function mcrypt_decrypt() is deprecated since PHP 7.1; use OpenSSL instead
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FILE: /http/dev.example.com/wp-content/plugins/download-manager/libs/class.Pagination.php
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FOUND 2 ERRORS AFFECTING 1 LINE
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136 | ERROR | Extension 'ereg' is deprecated since PHP 5.3 and removed since PHP 7.0 - use pcre instead.
136 | ERROR | Function eregi() is deprecated since PHP 5.3 and removed since PHP 7.0; use preg_match instead
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