Antigravity IDE - selecting default editor for '*.md' files breaks Implementation Plan presentation & features

Google Antigravity
1

Description:

In Antigravity IDE, selecting default editor for ‘*.md’ files completely breaks Implementation Plan presentation & features. After this change, Implementation Plan is displayed as any other * .md file, which means you can no longer make comments on the plan, the Proceed button is gone etc.

Steps to reproduce:

  1. Right click on any of *.md files in your project and select: Open with…
  2. Click on: Configure default editor for ‘*.md’…
  3. Select any editor from the list
  4. Now ask any of the LLMs to make you an Implementation Plan of any feature
  5. Open the Implementation Plan and see the broken UI

Version:

Antigravity IDE Version: 2.5.5
VSCode OSS Version: 1.107.0
Commit: ecfbad74d93962fc8ca485d93ab9b4f3d4cb…
Date: 2026-08-13T08:37:22.547Z
Electron: 39.2.3
Chromium: 142.0.7444.175
Node.js: 22.21.1
V8: 14.2.231.21-electron.0
OS: Darwin arm64 24.6.0
Language Server CL: 963923152