What PHP 8.5 changes for WordPress plugins

These are the functions, constants and settings that PHP 8.5 removes, deprecates or no longer ships, with what to use instead. A removed function or constant stops a plugin with a fatal error when that code runs. A deprecated one keeps working and logs a notice.

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Deprecated

curl_close(), curl_share_close(), imagedestroy(), xml_parser_free(), finfo_close(). The call has had no effect since PHP 8.0. Remove it.
mysqli_execute(). Use mysqli_stmt_execute().
socket_set_timeout(). Use stream_set_timeout().
DATE_RFC7231. Format the date in GMT yourself.
$http_response_header. Use http_get_last_response_headers().
report_memleaks, register_argc_argv. The setting is deprecated.

Bumpcheck also checks syntax changes, such as array offsets with curly braces and constructors named after their class. The full list is on the plugin page.