Meridian 1.39.0

July 10, 2026

Meridian follows your system's light and dark mode, you can RSVP to invitations, and launch stops beachballing on large mailboxes.

Light and dark mode — Meridian now follows your system appearance everywhere, switching live when macOS does, instead of mixing fixed light and dark panes. (Email content still renders on a light card — most mail is designed for it.)
RSVP to invitations — open any event you’re invited to and answer with Accept, Maybe, or Decline, for Google and Microsoft calendars. Your response syncs back to the organizer like it would from any calendar app.

Launch without the beachball — a background analysis pass was grinding through the entire mailbox on disk at every launch (over a minute of hidden work on large mailboxes) while the interface waited behind it. It now answers from an index in a fraction of a second, and the assistant stays out of the way while the app starts. The first launch after updating spends up to a minute building that index on very large mailboxes — every launch after gets the speedup.
Faster first sync for large Gmail accounts — new mailboxes bootstrap in much larger pages, so a big account finishes its initial sync several times sooner.
Fewer needless reloads — the activity picker and the menu-bar sections now refresh only when activities actually change.

Message bodies no longer disappear — archiving or reading a message could permanently erase its rich content, so opening it later showed only a plain-text preview. Bodies now survive every action. A small number of messages touched while the bug was live may still show text-only until the provider re-syncs them.
Outlook calendar edits reach the server — creating, editing, or deleting a Microsoft event from Meridian was silently failing; those changes now use the correct API paths and go through.
No more raw formatting codes — the assistant’s “All clear” card showed its internal grammar markup instead of “8 items handled.”
Quieter logs for dead calendar feeds — a calendar that can no longer be watched (deleted or access revoked) stops retrying its notifications every few minutes; Meridian falls back to polling and rechecks weekly.