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 by Jonathan Caudill and revived in September 2026 under a new maintainer; the current release is v1.6.0 (2026-11-12). Spaces can share one profile (website data store) or have their own, and the app imports Arc spaces, folders, favorites, extensions, routing rules and recent archived tabs. Store extensions get a compatibility layer (offscreen pages, notifications, idle, side panel and sign-in flows that WebKit lacks) and extension pages open in tabs. It builds for Apple Silicon only, and an iPhone/iPad companion is on the roadmap but not released.
Built-in AI
AI on by default
Sparkle button opens the Ask Nook chat, on by default; a Settings > AI toggle hides it (v1.6.0). Needs an API key, Ollama or on-device Apple Intelligence.
github.comBloat check
None found
No ads, wallet, feed or account; no analytics SDK in the latest 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 |
|---|---|---|---|
| SidebarVertical 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 |
| ProfilesProfiles 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 |
| FavoritesGlobal 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 TabsPinned 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 |
| Live foldersSidebar folders that fill and refresh themselves from an outside source, such as GitHub pull requests or an RSS feed. | ✓ | ✓ | A folder can follow GitHub PRs, issues or notifications, Asana tasks, or any RSS/Atom feed (New Live Folder menu).github.com |
| ArchiveAuto-archive tabsUnpinned tabs close automatically after a set time and stay recoverable in an archive. | ✓ | ✓ | Tabs left unopened for 12 h (adjustable, or never) move to an Archive, as do closed tabs; entries are kept 30 days.github.com |
| Theme pickerSpace 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 |
| PeekLink 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 |
| Little ArcMini windowA small, chrome-less window for links opened from other apps or a quick search. | ✓ | ✓ | Links from other apps open in a mini window by default (a setting turns it off); Air Traffic Control rules go first.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 |
| Air Traffic ControlLink 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 |
| BoostsSite 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 PiPAuto 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 |
| Mini playerMedia still playing in a tab you left keeps play/pause controls in the sidebar. | ✓ | ✓ | A sidebar card for media in a tab you left has previous, play/pause, next and mute buttons; it hides while that tab shows.github.com |
| Tab SwitcherRecent-tab switcherCtrl+Tab jumps back to the tab you used last and cycles in recently used order. | ✓ | ✓ | Ctrl+Tab opens a card of recent tabs; hold Control, press Tab to step, release to switch. Other keys on Next Tab keep sidebar order.github.com |
| Super CopyClean link copyA shortcut (⌘⇧C) copies the page URL with tracking parameters removed. | ◐ | ✓ | ⌘⇧C copies the current URL with a toast but does not strip it; a separate Privacy setting strips tracking when you open links.github.com |
| CaptureScreenshotsBuilt-in capture of a chosen area or element, and of the full page. | ◐ | ✓ | Per-site developer bar copies a visible-page screenshot; Pick Element (⌘⇧X, Developer Mode) saves an element image. No full-page capture.github.com |
Compatibility & migration
| Feature | Nook | Arc | Note |
|---|---|---|---|
| Arc importImports Arc spaces, pinned tabs and folders. | ✓ | – | Imports Arc spaces, folders, order, favorites, colors, extensions, routing rules and the last 30 days of archived tabs.github.com |
| Chrome extensionsInstalls extensions from the Chrome Web Store. | ✓ | ✓ | Chrome, Edge and Firefox store extensions via WKWebExtension; since v1.6.0 a compatibility layer fills in APIs WebKit lacks (offscreen, notifications, sign-in).github.com |
| DRM streamingNetflix, Disney+, Spotify web and other DRM video/audio play, through Widevine or, on WebKit, FairPlay. Chromium forks need a Google Widevine licence; FairPlay counts once a major service is confirmed playing in the app. | ? | ✓ | No Widevine; a maintainer says WebKit's built-in FairPlay covers DRM, but no playback on any service is 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; on for new installs, older installs keep their choice.github.com |
| Custom ShortcutsShortcut editorMost browser keyboard shortcuts can be remapped in Settings. | ✓ | ✓ | Settings > Shortcuts lists about 60 actions, each with a recorder to rebind it, plus Reset to Defaults.github.com |
More Arc features
Arc features shown but not counted in the score, because almost no replacement has them or only a few people need them.
| Feature | Nook | Arc | Note |
|---|---|---|---|
| EaselsA shareable canvas of live page captures, notes and drawings. | ✕ | ◐ | No easel or board code; the sidebar create menu offers space, folder, live folder, Boost, split and tab only.github.com |
| Shared CollectionsShared spaces & foldersShare a Space, folder or set of tabs as a link anyone can open, or another user can add to their sidebar. | ◐ | ✓ | Multi-selected tabs offer Copy N Links as text; a single tab has Copy Link as Markdown and Share. No shareable Space or folder link.github.com |
| PreviewsWeb app previewsHover a pinned Gmail, Calendar or other web app to glance at it; a pinned calendar shows the next meeting with Join. | ✕ | ✓ | Only a generic link-preview card exists; no hover glance at pinned Gmail, Calendar or similar apps, and no unread badges.github.com |
| Developer modeA developer view that turns on by itself for localhost: full URL, quick DevTools and dev tools in reach. | ✓ | ✓ | Per-site Developer Mode (site panel) shows a bar with full URL, screenshot, console, network and inspector; global toggle adds dev badges on local hosts.github.com |
Extension support
Which extension formats and stores run, beyond the Chrome Web Store row above.
| 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 manifests load 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; WebKit has no blocking webRequest, 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 |