same issue here
deprecated: Function seems_utf8 is deprecated since version 6.9.0! Use wp_is_valid_utf8() instead. in /var/docs/server.tst/public/wp-includes/functions.php on line 6173
\bbpress\bbpress.2.6.14\bbpress\includes\common\formatting.php line 810 !
Just change it to wp_is_valid_utf8 that will make the warning message go away.
FILE: /bbpress/includes/common/formatting.php
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FOUND 0 ERRORS AND 2 WARNINGS AFFECTING 2 LINES
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810 | WARNING | seems_utf8() has been deprecated since WordPress version 6.9.0. Use wp_is_valid_utf8() instead. (WordPress.WP.DeprecatedFunctions.seems_utf8Found)
811 | WARNING | Function utf8_encode() is deprecated since PHP 8.2; Use mb_convert_encoding(), UConverter::transcode() or iconv instead (PHPCompatibility.FunctionUse.RemovedFunctions.utf8_encodeDeprecated)
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