New Desktop App

[princebaretto99]

Summary

Replaces the Electron-based Percy Desktop App with a lightweight, native Node.js desktop app (desktop-app/) — no Electron, no Chromium runtime bundled into the installer. It keeps the same job (start/stop a local Percy server for the Chrome extension) but ships as a proper double-clickable app with a real menu bar icon, and fixes several extension-side bugs surfaced while getting the new app working end-to-end with current @percy/cli.

What's new: desktop-app/

• Native menu bar UI, not Electron. On macOS the tray icon is a ~100-line Swift helper (native/tray.swift), compiled as a universal arm64+Intel binary and driven by the Node process over stdin/stdout JSON. Windows/Linux use the small systray2 native helper. Menu shows live "Percy server: running/stopped" status, "Stop Percy server", and "Quit".
• Packaged with @yao-pkg/pkg, not Electron — Node is bundled into the executable, so end users don't need Node/npm installed. npm run build:mac produces a proper .app bundle (LSUIElement, no Dock icon, ad-hoc signed); build:win / build:linux produce standalone executables.
• Same HTTP contract the extension already expects on localhost:3778:
  • POST /percy/start — starts the local Percy server (spawns the standalone Percy CLI, downloaded once from the official percy/cli GitHub releases into ~/.percy-desktop-app/bin)
  • POST /percy/snapshot — proxies a snapshot upload to the Percy server (see "Why a proxy" below)
  • POST /percy/stop — stops the Percy server
  • GET /healthcheck — app + Percy server status
• Prefers the user's installed Chrome/Chromium/Edge over downloading Percy's own Chromium, via PERCY_BROWSER_EXECUTABLE — faster startup, no ~150MB browser download, and avoids an Apple Silicon/Rosetta browser-launch timeout Percy's bundled x86_64 Chromium hit in testing.
• Security hardening on the local HTTP server: validates the Host header (defends against DNS rebinding) and rejects state-changing requests (/percy/start, /percy/snapshot, /percy/stop) from non-extension web origins, since any webpage can otherwise reach localhost.
• Logs to ~/.percy-desktop-app/app.log (a double-clicked app has no terminal).

See desktop-app/README.md for build/run instructions and full API docs.

Extension-side fixes (utils/percy-utils.ts)

Getting a real end-to-end build working against current @percy/cli surfaced a few bugs, unrelated to Electron vs. Node but blocking either desktop app:

1. MV3 service worker was dying mid-finalize. Percy.finalise() can legitimately run for 30–60s+ (Percy server startup + snapshot uploads), but a pending fetch doesn't reset Chrome's ~30s service worker idle timer — only extension API calls do. Added a chrome.runtime.getPlatformInfo() keepalive ping for the duration of finalise().
2. stopPercy() used GET; Percy CLI's /percy/stop only accepts POST. Was silently 404ing and leaving builds stuck in "Receiving".
3. Percy CLI rejects cross-origin requests to /percy/snapshot and /percy/stop (loopback-origin-only check, added for CSRF hardening in newer CLI versions — the extension's chrome-extension:// origin fails it). Routed both calls through the desktop app's proxy endpoints instead of hitting Percy directly; the desktop app forwards them origin-less, server-to-server.
4. Removed a stray import { it } from "node:test" accidentally left in the file.

Testing

• Verified the local HTTP server's origin/host checks (web-origin requests get 403, spoofed Host gets 403, extension-origin requests pass).

Manual pass (capture snapshot → finalize → desktop app starts Percy → snapshots upload → build appears on Percy dashboard with received snapshots → server stops) against the packaged app, per OS:

• macOS
• Windows
• Linux

Not done / follow-ups

• macOS build is ad-hoc signed; for public distribution this needs a Developer ID signature + notarization.
• Windows build (@yao-pkg/pkg executable) opens a console window alongside the tray icon — a pkg limitation.