GitHub Releases Copilot Plugin Version 1.20.0 for JetBrains IDEs

GitHub shipped Copilot plugin version 1.20.0 for JetBrains IDEs on October 28. The release introduces Copilot Fusion model tiers, general availability for local sandboxing, and makes the Microsoft Copilot agent harness the default where available.

Copilot Fusion replaces the Auto model option and rolls out gradually with Standard, High, and Max tiers. Copilot selects a single model or combines multiple options based on task effort, and Fusion use receives a 30% discount for the first 30 days.

Local sandboxing moves to general availability, providing a restricted execution boundary for agentic workflows on the user's machine. Tools and commands run with limited system access according to policies defined by developers or organizations.

Next edit suggestions (NES) are also generally available, featuring improved suggestion quality, context awareness, and inline review tools. Inline completions and NES coordinate more closely, generating follow-up suggestions after you accept a completion.

New workflow additions include a session sidebar button for side-by-side views, a default permission mode setting for new sessions, and a top-level placement for GitHub Copilot in IDE settings. When both providers are enabled, Copilot appears ahead of Local in the agent picker. Hovering over an agent turn displays generation time, completion time, and per-model token usage.

Version 1.20.0 includes fixes for cancellation recovery, edit reliability, and selected-code context, alongside resolutions for Windows and WSL customization access, language server restarts affecting prompt templates, and IDE responsiveness.