PHP 8 compatibility

I had problems with PHP 8 on this website and the report shows these problems.

..aikidosarasota.com/html/wp-content/plugins/wp-mail-smtp/vendor_prefixed/phpseclib/phpseclib/phpseclib/Crypt/Common/SymmetricKey.php

FOUND 26 ERRORS AFFECTING 20 LINES

1142 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1174 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1177 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1182 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1190 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1199 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1201 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1504 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1531 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1536 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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1546 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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2053 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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2150 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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2151 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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2155 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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2251 | ERROR | The constant "MCRYPT_MODE_ECB" is deprecated since PHP 7.1 and removed since PHP 7.2
2251 | ERROR | The constant "MCRYPT_MODE_CBC" is deprecated since PHP 7.1 and removed since PHP 7.2
2251 | ERROR | The constant "MCRYPT_MODE_CFB" is deprecated since PHP 7.1 and removed since PHP 7.2
2251 | ERROR | The constant "MCRYPT_MODE_NOFB" is deprecated since PHP 7.1 and removed since PHP 7.2
2251 | ERROR | The constant "MCRYPT_MODE_OFB" is deprecated since PHP 7.1 and removed since PHP 7.2
2251 | ERROR | The constant "MCRYPT_MODE_STREAM" is deprecated since PHP 7.1 and removed since PHP 7.2
2252 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
| | instead
2253 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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2258 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
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2258 | ERROR | The constant "MCRYPT_MODE_ECB" is deprecated since PHP 7.1 and removed since PHP 7.2
2263 | ERROR | Extension 'mcrypt' is deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl/mcrypt once available
| | instead

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