Postbox

Postbox is a desktop email client for power users, built on Mozilla’s Thunderbird codebase but enhanced with a modern UI and advanced features. It supports multiple accounts and offers flexible tagging, quick search, and pre-written response snippets. The Focus Pane filters messages by attributes (e.g., unread + label = “Projects”). Built-in anti-tracking helps block remote images and trackers. Postbox’s integration with calendars or to-do apps is somewhat limited, but it suits heavy email users wanting a robust desktop client that excels at organization and speed on Mac or Windows.