GitHub Copilot in JetBrains gets Fusion, generally available local sandboxes and next edit suggestions

GitHub's JetBrains update brings Copilot Fusion to JetBrains IDEs. Fusion replaces the current Auto model option and is rolling out gradually to all Copilot users; GitHub says its use is discounted 30% for the first 30 days.

• Local sandboxes are generally available: tools and commands started by Copilot run with restricted access to the filesystem, network and credentials, under policies set by the developer or organization.
• Next edit suggestions are generally available, with better suggestion quality and context awareness.
• The Microsoft Copilot agent harness becomes the default harness for all users when available.
• Smaller changes: a session sidebar button to open sessions side by side, a default permission mode for new sessions, Copilot at the top level of IDE settings, and per-turn completion time, generation time and per-model token usage on hover.