Synology DownloadStation Chrome Extension

A Chrome extension (Manifest V3) to manage your Synology DownloadStation from the browser.

Features

• Right-click → "Send to DownloadStation" — Add any link or page URL as a download task
• Toolbar popup — View active/finished/error tasks with real-time progress bars; pause, resume, or delete tasks
• File open — Double-click a finished task's filename to download it directly to your browser
• Offline queue — Tasks sent while the NAS is unreachable are queued locally and flushed automatically on reconnect (or manually via the popup banner)
• QuickConnect & HTTP support — Connect using a QuickConnect ID, direct QuickConnect URL, plain HTTP, or standard HTTPS
• Auto API discovery — Queries SYNO.API.Info on login to find the correct endpoint path and version for each API (compatible with DSM 5 / 6 / 7)
• Options page — Configure NAS URL, credentials, and default download destination

Prerequisites

• Synology NAS with DSM 6.x or 7.x
• DownloadStation package installed and enabled
• Node.js 18+ and npm
• Chrome (or any Chromium-based browser)

Setup

1. Install & Build

npm install
npm run build

2. Load in Chrome

1. Open chrome://extensions/
2. Enable Developer mode (top-right toggle)
3. Click "Load unpacked"
4. Select the dist/ folder

3. Configure

Click the extension icon → ⚙ Settings and enter:

Field	Example
NAS URL	https://192.168.1.100:5001
Username	admin
Password	your password
Default Destination	/downloads (optional)

Supported URL formats

Type	Example
HTTPS	https://192.168.1.100:5001
HTTP	http://nas:5000
QuickConnect direct	solidlime.direct.quickconnect.to
QuickConnect ID	solidlime or quickconnect.to/solidlime

Self-Signed Certificates

If your NAS uses a self-signed SSL certificate, you may see a network error. To fix:

1. Open your NAS URL in Chrome (e.g. https://192.168.1.100:5001)
2. Click Advanced → Proceed anyway to trust the certificate
3. The extension will now be able to connect

HTTP connections (http://) do not require any certificate setup.

Offline Queue

When the NAS is unreachable (network down, NAS sleeping, etc.), any URL you right-click and send will be saved in an offline queue stored in chrome.storage.local.

The queue is flushed automatically on browser startup. If the popup is open and the NAS comes back online, a yellow banner appears with a "Send now" button to flush all queued tasks immediately.

Queued tasks are never lost — they persist until successfully sent to DownloadStation.

Downloading Files

In the popup's Finished tab, filenames appear as clickable links.
Double-click a filename to download it directly to your browser's default downloads folder.

Development

npm run build         # Full build (icons + TypeScript)
npm run build:watch   # Auto-rebuild on file changes
npm run typecheck     # TypeScript type-check only (tsc --noEmit)
npm run clean         # Remove dist/

Chrome loads the extension from the dist/ directory. Reload it after each build in chrome://extensions/.

Tech Stack

• TypeScript + esbuild (Manifest V3)
• Synology WebAPI — auto-discovered via SYNO.API.Info at login
  • SYNO.API.Auth v3–v7
  • SYNO.DownloadStation.Task v1–v3
  • SYNO.FileStation.Download v2
• chrome.storage.local for settings and offline queue persistence
• chrome.downloads API for in-browser file downloads

Notes

• 2FA (OTP) is not supported. Disable 2FA for the account used by this extension.
• Passwords are stored in chrome.storage.local (unencrypted, local to your Chrome profile).
• The client/ directory is a local convenience copy of dist/ and is not tracked by Git.