Megastructure Arc · July 27, 2026
Arc 1.6.6
Arc 1.6.6 makes file drag-and-drop and picker attachments immediate by default, while preserving the safeguards that keep workspace files intact.
Previous release
Files attach without interruption
Windows 10/11 (64-bit), or macOS 11+ on Apple Silicon.
Highlights
- Drag a file into the composer or choose it with the file picker and its attachment chip appears immediately, without a copy confirmation dialog.
- Teams that prefer an extra check can enable “Ask before copying attached files” in General settings. It remains off by default for both new and existing installs.
Fixes and refinements
- Arc still revalidates the destination, reserves each attachment safely, never overwrites an existing file, verifies content hashes, rolls back incomplete copies, and rechecks authorization when you send.
System requirements
Windows 10/11 (64-bit), or macOS 11+ on Apple Silicon.