First impression, it automatically logged into my google account on first startup without notification. Here's copilots explanation:

Short answer: AionUi auto-detected an existing Google OAuth credential on your machine and used it to show the account email in Settings. It does this by asking the main process whether a cached OAuth identity exists (and if so returns the account email) — no mysterious network phone‑home is required for that step.

How it works (sequence)

• The Settings UI (Gemini settings panel) calls ipcBridge.googleAuth.status to check Google login state.
• File: src/renderer/components/settings/SettingsModal/contents/GeminiModalContent.tsx (loadGoogleAuthStatus uses ipcBridge.googleAuth.status)
• The IPC provider is handled in the main/process side (authBridge). That handler first calls getOauthInfoWithCache and, if that fails, it looks for a credentials file and reads it to see whether there is a refresh_token / access_token and an email.
• File: src/process/bridge/authBridge.ts — the google auth status/login handlers read cached oauth info and the credentials file (checks for refresh_token and returns account email)
• Link: https://github.com/iOfficeAI/AionUi/blob/31558ee457b2874bac256cf010ed965ddab535e2/src/process/bridge/authBridge.ts
• The app also checks for standard Gemini CLI credential files (e.g. \~/.gemini/oauth_creds.json) as a fallback when deciding which provider to use.
• Example: src/process/channels/actions/SystemActions.ts reads \~/.gemini/oauth_creds.json and uses it if present
• Link: https://github.com/iOfficeAI/AionUi/blob/31558ee457b2874bac256cf010ed965ddab535e2/src/process/channels/actions/SystemActions.ts

Why your email appeared on first run

• You already had Google OAuth credentials on your machine (for example created earlier by:
• gemini auth login (the Gemini/Vertex CLI),
• a previous AionUi install, or
• another tool that writes the same creds file).
• AionUi detected those credentials and returned the cached account email to the renderer, which populated the Settings field.