Redirect URI mismatch on Antigravity

[lukpanek]

Describe the bug

The extension is currently not working on Antigravity. When trying to log in to the extension, the OAuth redirect responds with invalid_request error. Antigravity has it's own scheme, so I think it just might be a misconfiguration in GitHub OAuth app (the redirect URI is antigravity://posthog.posthog-vscode/auth/callback).

Steps to reproduce

1. Install the extension
2. Click on "Sign in with PostHog" button in extension setup screen
3. Select an EU PostHog Cloud
4. Get redirected to an error page

Expected behavior

The login flow should be correctly handled and I should be taken back to Antigravity and be logged into the extension.

Environment

• VS Code version: 1.107.0 (Antigravity 1.23.2)
• Extension version: 0.71.1
• OS: MacOS 26.1
• PostHog instance: EU Cloud

Screenshots

[fercgomes]

Thanks for raising this issue! I'll take a look at it and will let you know.