W3 Total Cache Pro 2.8.0

n/a

* Fix: Correct interpolation of a symlinked cache directory
* Fix: Memcached test using SASL authentication
* Fix: Multi-site authorization request returning to incorrect URL

Fix: PHP 8 compatibility: Invalid return type if Browser Cache is disabled
Fix: Added AWS SNS message classes (aws/aws-php-sns-message-validator)
Fix: PageSpeed service: messages and escaping
Fix: Image Service meta query handling
Update: Dependency version updates
Update: Content-Security-Policy (CSP) and Content-Security-Policy-Report-Only (CSPRO) header field configuration