WP Mailster v1.9.0 – WP Mailster

[Improvement] Raise the minimum PHP version from 5.6 to 7.4
[Feature] Add Google and Microsoft OAuth 2.0 authentication for incoming IMAP mailboxes
[Feature] Add a Webklex mailbox backend for IMAP access without the PHP IMAP extension (requires PHP 7.4 or newer)
[Improvement] Support PHP 8.4 and 8.5 through the bundled Webklex PHP-IMAP library, without requiring the PHP IMAP extension for IMAP mailboxes
[Improvement] Improve MIME header decoding, attachment filenames, inline images and nested email handling
[Improvement] Improve calendar invitation handling and show event summaries
[Improvement] Prioritize recipients with fewer send errors when processing the mail queue
[Improvement] Improve mailbox connection diagnostics and OAuth connection status feedback
[Bug Fix] Avoid PHP warnings
[Bug Fix] Check the bundled Webklex PHP requirement before loading its dependencies