Browser Compatibility

FlowPick's feature availability across different browsers depends on browser support for modern Web APIs. This document provides detailed feature compatibility matrix and fallback strategy explanations.

Quick Browser Check

Before starting to use FlowPick, you can quickly determine if your browser meets requirements through following methods:

Browser Support Overview

Feature Availability Quick Reference

Following table shows browser support status by feature dimension for quick lookup:

✅ Full support · ⚠️ Partial support (with fallback) · 🚧 In development · ❌ Not supported

API Compatibility Matrix

FlowPick depends on following browser APIs. Different browser support directly affects feature availability.

Core APIs

Advanced APIs

Feature Fallback Strategies

When a browser doesn't support certain API, FlowPick automatically falls back to alternative solution to ensure core functionality is always available.

File Write Fallback Chain

File System Access API (Best)
    ↓ Fallback when unavailable
StreamSaver.js (Streaming write)
    ↓ Fallback when unavailable
Blob + <a> download (Memory write, has size limit)

Impact when File System Access API unavailable:

• Cannot use "Select Save Directory" feature
• Need to manually select save location each time (popup mode)
• Large files (>1.5GB) may fail due to memory limitations

Impact when StreamSaver.js unavailable:

• File fully loaded into memory before triggering download
• Subject to Blob size limit (1.5GB hard cap)
• Warning displayed before large file downloads

FFmpeg Multi-threading Fallback

SharedArrayBuffer available → Multi-threaded FFmpeg (Fast)
    ↓ Fallback when unavailable
SharedArrayBuffer unavailable → Single-threaded FFmpeg (Slower)
    ↓ Fallback when FFmpeg loading fails
TS format → Direct binary concatenation (Fastest, no FFmpeg needed)

Impact when SharedArrayBuffer unavailable:

• FFmerge speed reduced by ~40-60%
• Functionality completely unaffected, only slower
• Selecting TS output format can completely bypass FFmpeg

Notification Fallback

Notifications API available → System desktop notification
    ↓ Fallback when unavailable
In-app status prompt

Security Header Requirements

FlowPick website needs following HTTP response headers configured to enable all features:

Required Security Headers

Cross-Origin-Opener-Policy: same-origin
Cross-Origin-Embedder-Policy: require-corp

These two headers are prerequisites for SharedArrayBuffer, affecting FFmpeg multi-threaded mode.

Recommended Security Headers

X-Frame-Options: SAMEORIGIN
Cross-Origin-Resource-Policy: same-origin

These headers ensure StreamSaver.js's mitm.html and Service Worker work properly.

Deployment Checklist

If you deploy FlowPick website yourself, please confirm:

• / path returns Cross-Origin-Opener-Policy: same-origin
• / path returns Cross-Origin-Embedder-Policy: require-corp
• /mitm.html accessible normally
• /streamsaver-sw.js accessible normally with correct Service-Worker-Allowed header
• /_nuxt/* static resource paths have correct COEP/COOP headers set

Detailed Browser Descriptions

Google Chrome (Recommended)

Version requirement: 86+

All features supported:

• File System Access API (directory selection, persistent permissions)
• SharedArrayBuffer (requires COEP/COOP headers)
• StreamSaver.js
• FFmpeg WASM multi-threading
• All extension features

Known issues: None

Microsoft Edge (Recommended)

Version requirement: 86+

All features supported: Same as Chrome (based on Chromium)

Known issues:

• Some enterprise policies may disable File System Access API
• Extension needs to be installed from Edge Add-ons store

Firefox (In Development)

Current status: Extension version in development, online tools partially available

Limitations:

• Does not support File System Access API
• Does not support showSaveFilePicker
• SharedArrayBuffer requires COEP/COOP headers (Firefox 79+)
• Limited StreamSaver.js support

Fallback behavior: All downloads use Blob mode

Safari (Not Recommended)

Current status: Extension version not supported

Limitations:

• Does not support File System Access API
• Does not support SharedArrayBuffer
• Does not support showSaveFilePicker
• Does not support showDirectoryPicker
• Limited WebAssembly support
• Restricted Service Worker functionality

Fallback behavior: Only supports basic Blob download mode, FFmpeg may fail to load

Mobile Browsers

FlowPick is primarily designed for desktop browsers. Mobile browser extension support is limited:

Mobile limitations:

• Does not support File System Access API
• Stricter memory limitations
• Download management experience inferior to desktop

How to Choose Browser

FAQ

Why don't I see "Select Save Directory" button?

"Select Save Directory" relies on File System Access API, requires Chrome/Edge 86+. If your browser version meets requirements but still doesn't show it, enterprise policy may have disabled this API. Will automatically fall back to Blob download mode.

What if FFmpeg merge is very slow?

FFmpeg multi-threaded mode requires SharedArrayBuffer, which requires website to configure COEP/COOP security headers. If you deploy FlowPick yourself without configuring these headers, FFmpeg will automatically fall back to single-threaded mode, reducing speed by ~40-60%.

Solutions:

1. Use FlowPick official website (security headers already configured)
2. Select TS output format to skip FFmpeg merging
3. Configure COEP/COOP headers when deploying yourself

Can I use FlowPick on mobile?

Mobile browsers don't support extensions, but can use Online Tools. However, mobile devices have memory limitations and missing APIs, making large file download experience poor. Recommend completing downloads on desktop.

When will Firefox have full support?

Firefox extension version is under development. Firefox's Manifest V3 support is still being improved, and File System Access API currently has no implementation plan in Firefox. Before extension release, Firefox users can use online tools.

Related Documentation

• Installation Guide — Chrome/Edge extension installation steps
• Online Tools — Web-based downloader requiring no installation
• Download Engine Architecture — Write strategies and fallback logic details
• Format Conversion — FFmpeg WASM engine and dual engine architecture
• Video Sniffing — Extension auto-detection principles
• Batch Download — Queue management and concurrency control
• Configuration Reference — Download behavior configuration items
• Common Issues Troubleshooting — Diagnosis of browser-related issues
• Known Issues — Known limitations per browser