Summary of Issue with WebClient.php

After upgrading to Joomla 5.X from previous versions, and updating to PHP 8.2.X, there is an error in the error log for WebClient.php. The line numbers vary.
stripos(): Passing null to parameter #1 ($haystack) of type string is deprecated in /home/name/public_html/libraries/vendor/joomla/application/src/Web/WebClient.php on line XXX.

Steps to reproduce the issue

View PHP Error log for Joomla site with PHP 8.2.X.
Locate the error:
/home/name/public_html/libraries/vendor/joomla/application/src/Web/WebClient.php on line XXX.

Open the file /home/name/public_html/libraries/vendor/joomla/application/src/Web/WebClient.php

Find this code:
// Attempt to detect the browser type. Obviously we are only worried about major browsers.
if ((\stripos($userAgent, 'MSIE') !== false) && (\stripos($userAgent, 'Opera') === false)) {
$this->browser = self::IE;
$patternBrowser = 'MSIE';
} elseif (\stripos($userAgent, 'Trident') !== false) {
$this->browser = self::IE;
$patternBrowser = ' rv';
} elseif (\stripos($userAgent, 'Edge') !== false) {
$this->browser = self::EDGE;
$patternBrowser = 'Edge';
} elseif (\stripos($userAgent, 'Edg') !== false) {
$this->browser = self::EDG;
$patternBrowser = 'Edg';
} elseif ((\stripos($userAgent, 'Firefox') !== false) && (\stripos($userAgent, 'like Firefox') === false)) {
$this->browser = self::FIREFOX;
$patternBrowser = 'Firefox';
} elseif (\stripos($userAgent, 'OPR') !== false) {
$this->browser = self::OPERA;
$patternBrowser = 'OPR';
} elseif (\stripos($userAgent, 'Chrome') !== false) {
$this->browser = self::CHROME;
$patternBrowser = 'Chrome';
} elseif (\stripos($userAgent, 'Safari') !== false) {
$this->browser = self::SAFARI;
$patternBrowser = 'Safari';
} elseif (\stripos($userAgent, 'Opera') !== false) {
$this->browser = self::OPERA;
$patternBrowser = 'Opera';
}

Fix the issue

Replace it with this code:
// Attempt to detect the browser type. Obviously we are only worried about major browsers.
if ($userAgent !== null) {
if ((stripos($userAgent, 'MSIE') !== false) && (stripos($userAgent, 'Opera') === false)) {
$this->browser = self::IE;
$patternBrowser = 'MSIE';
} elseif (stripos($userAgent, 'Trident') !== false) {
$this->browser = self::IE;
$patternBrowser = ' rv';
} elseif (stripos($userAgent, 'Edge') !== false) {
$this->browser = self::EDGE;
$patternBrowser = 'Edge';
} elseif (stripos($userAgent, 'Edg') !== false) {
$this->browser = self::EDG;
$patternBrowser = 'Edg';
} elseif ((stripos($userAgent, 'Firefox') !== false) && (stripos($userAgent, 'like Firefox') === false)) {
$this->browser = self::FIREFOX;
$patternBrowser = 'Firefox';
} elseif (stripos($userAgent, 'OPR') !== false) {
$this->browser = self::OPERA;
$patternBrowser = 'OPR';
} elseif (stripos($userAgent, 'Chrome') !== false) {
$this->browser = self::CHROME;
$patternBrowser = 'Chrome';
} elseif (stripos($userAgent, 'Safari') !== false) {
$this->browser = self::SAFARI;
$patternBrowser = 'Safari';
} elseif (stripos($userAgent, 'Opera') !== false) {
$this->browser = self::OPERA;
$patternBrowser = 'Opera';
}
}

This fixes the error.