Nook
Open-source, Arc-style WebKit browser for macOS with spaces, shareable profiles and Arc import.
Nook is a free, GPL-3.0 browser for macOS built on Apple's WebKit, with a sidebar-first layout and Arc-like spaces. It was started in 2025 and revived in September 2026 under a new maintainer; the current release is v1.4.0 (2026-10-28). Spaces can share one profile (website data store) or have their own, and the app imports Arc spaces, folders, favorites and extensions. It builds for Apple Silicon only, and an iPhone/iPad companion is on the roadmap but not released.
74% Arc feature parity (yes = 1, partial = ½).
Built-in AI
AI on by default
Sparkle button opens the Ask Nook chat, shown by default. It needs an API key, Ollama or on-device Apple Intelligence (macOS 26), which is auto-picked.
github.comNot counted in Arc parity: some people want AI, some avoid it.
Bloat check
None found
No ads, wallet, feed or account; no analytics SDK in the v1.4.0 source, and the site pledges no browsing-data collection. Only Sparkle update checks.
browsewithnook.comAds, crypto, paid upsells, news feeds, default-on telemetry, required accounts.
Organization
| Feature | Nook | Arc | Note |
|---|---|---|---|
| Vertical sidebarTabs live in a vertical sidebar that is the main tab UI and can be hidden. | ✓ | ✓ | Sidebar-first design with vertical tabs; sidebar can be dragged hidden.github.com |
| SpacesSeveral workspaces per window, each with its own pinned and open tabs, switched by swipe or shortcut. | ✓ | ✓ | Each space has its own favorites, pinned and tabs sections; Ctrl+1-9 and swipe to switch.github.com |
| Profiles per Space (shareable)Each Space can use its own browser profile (separate cookies, logins, history), and one profile can be shared by several Spaces. | ✓ | ✓ | New Space picks a new profile or an existing one to share logins (v1.3.0); profile = shared data store.github.com |
| Global favoritesPinned icons at the top of the sidebar shared by every Space (Zen calls them Essentials). | ◐ | ✓ | Favorites grid is stored per space, not shared across all spaces.github.com |
| Pinned tabs & foldersPer-space pinned tabs that act like bookmarks, with nested folders. | ✓ | ✓ | Per-space pinned section with folders; Arc import keeps folders and order.github.com |
| Auto-archive tabsUnpinned tabs close automatically after a set time and stay recoverable in an archive. | ◐ | ✓ | v1.4.0 only unloads idle tabs (Power Saving/Standard/Performance); no archive. Archive is unreleased on develop.github.com |
| Space themesPer-space colour or gradient themes. | ✓ | ✓ | Space themes with colors, texture and light or dark (v1.4.0).github.com |
Browsing
| Feature | Nook | Arc | Note |
|---|---|---|---|
| Split ViewTwo or more tabs side by side in one window. | ◐ | ✓ | One left/right pair per window with a resizable divider; no more than two panes.github.com |
| Link previewOpen a link in an overlay without leaving the current page (Zen calls it Glance). | ✓ | ✓ | Peek overlay opens for cross-site links from favorites/pinned tabs, or on Option-click.github.com |
| Mini windowA small, chrome-less window for links opened from other apps or a quick search. | ✓ | ✓ | Links from other apps open in a small mini window; Air Traffic Control rules take precedence.github.com |
| Command barA ⌘T palette that searches tabs, history, bookmarks and browser commands. | ◐ | ✓ | Palette suggests tabs, history (incl. page text), URLs and searches; no browser commands found.github.com |
| Link routingRules that send links from other apps to a chosen space or profile. | ✓ | ✓ | Air Traffic Control rules send domain/path links to a chosen space, including links from other apps.github.com |
| Site customizationPer-site custom CSS/JS, or zapping elements off a page. | ✓ | ✓ | Per-site Boosts: CSS, optional script (off by default), colors/fonts and Zap element hiding (v1.4.0).github.com |
| Auto picture-in-picturePlaying video pops out into picture-in-picture automatically when you switch tabs. | ✓ | ✓ | Opt-in setting (off by default): playing video moves to sidebar or system PiP when you switch tabs.github.com |
Compatibility & migration
| Feature | Nook | Arc | Note |
|---|---|---|---|
| Arc importImports Arc spaces, pinned tabs and folders. | ✓ | – | Imports Arc spaces, folders, order, favorites, colors and extensions; routing rules and archive not yet.github.com |
| Chrome extensionsInstalls extensions from the Chrome Web Store. | ✓ | ✓ | Installs from Chrome Web Store (also Edge and Firefox stores) via WKWebExtension.github.com |
| DRM (Widevine)Netflix, Disney+, Spotify web and other DRM video/audio play. Chromium forks need a Google Widevine licence. | ◐ | ✓ | No Widevine; maintainers rely on WebKit's built-in FairPlay. Per-service playback not documented.github.com |
| PasskeysWebAuthn passkeys, Touch ID and the system/iCloud keychain. | ◐ | ✓ | Passkeys via password managers only; iCloud Keychain platform passkeys are suppressed in code.github.com |
| SyncSpaces, pinned tabs and settings sync across devices. | ✕ | ✓ | No sync: SwiftData CloudKit is off in code; iCloud sync for spaces and tabs is only a roadmap item.github.com |
| Mobile appiPhone, iPad or Android app that shares spaces with desktop. | ✕ | ◐ | iOS target (NookiOS) is in the repo but not released; companion app is on the roadmap.github.com |
Extras
| Feature | Nook | Arc | Note |
|---|---|---|---|
| Built-in ad blockerAd and tracker blocking without installing an extension. | ◐ | ✓ | Built-in adblock-rust blocker with EasyList/uBlock lists; adBlockerEnabled defaults to off.github.com |
Extension support
Which extension formats and stores run, beyond the Chrome Web Store row above. Not counted in Arc parity.
| Feature | Nook | Arc | Note |
|---|---|---|---|
| Manifest V2 extensionsThe older extension format Chrome removed in 2025. Needed for full uBlock Origin and other extensions that block requests. | ◐ | ✕ | MV2 loads on WebKit, but there is no blocking webRequest, so full uBlock Origin cannot block.github.com |
| Manifest V3 extensionsThe current extension format used by the Chrome Web Store (and supported by Firefox and Safari). | ✓ | ✓ | MV3 runs on WebKit's WKWebExtension; Nook wakes service workers that die after ~5 min idle.github.com |
| Firefox add-onsAdd-ons from addons.mozilla.org or .xpi files install and run. | ✓ | ✕ | Installs from addons.mozilla.org; webRequestBlocking is ignored, so Firefox uBlock Origin cannot block.github.com |
| Safari extensionsSafari web extensions (the App Store extension apps Safari uses) install and run. | ✓ | ✕ | Finds installed Safari .appex extensions and installs them; also accepts .appex and .app files.github.com |