Thunderbird 138 adds in-notification email controls, enhanced high-contrast mode, and more

Mozilla has rolled out Thunderbird 138, delivering several significant upgrades to its free, open-source email client. The most notable change is the revamped new-mail alert that now features disposition buttons embedded directly in the notification. With this, users can archive, delete, or reply to emails instantly without needing to open the main Thunderbird window, streamlining everyday workflow.

For those using macOS, notification customization options have been introduced in the settings' panel. This gives users granular control over how and what notifications appear, further personalizing the alert experience. Another subtle but important change involves high-contrast modes on macOS and Linux, as the default color overrides have been fine-tuned to enhance accessibility.

Thunderbird 138 also resolves a series of user-reported bugs, including the issue where macOS notifications displayed two logos, corrections to the displayed day of week in emails, improved message preview truncation within notifications, and better light/dark theme handling. These fixes combine to ensure greater reliability and usability for all users.