Overview
The missing macOS web app wrapper: a tiny native Swift shell that opens a specific URL in a WebKit window with as little visible chrome as macOS will allow. No address bar, no tab strip, no bookmark bar — just the page in a native window. Safari Web Apps bring too much browser furniture; Web App Viewer brings none. Can install any URL as a standalone app in ~/Applications with its own icon, bundle identifier, and preference store.
How it works
Each window is a WKWebView that fills the frame. An invisible draggable strip at the top (right of the traffic lights) lets you move the window even with the titlebar suppressed. Traffic-light controls and scrollbars appear only while the pointer is over the window. Same-origin links stay inside the app, new-window links open another app window, and external links go to Safari. The app installs itself as a standalone per-URL app via a drop/paste window with icon and name customization.
Features
Chromeless WebKit window
No toolbar, no address bar, no fullscreen frame — just the page.
App installer
Installs any URL as its own macOS app in ~/Applications with manifest/favicon icon selection and custom naming.
User Scripts
Per-URL JavaScript injection from Preferences — regex URL matching, syntax-highlighted editor, enable/disable per script.
Foreground notifications
Supports the standard Web Notification API while the app is running.
Share Extension + macOS Service
"Open in Web App Viewer" in the Services menu, Share sheet, and webappviewer://open?url=… URI scheme.
Web Inspector
View menu, Option-Command-I, context menu, or Safari Develop menu — embedded views are inspectable.
Downloads + drops
File downloads to ~/Downloads; accepts .webloc, public.url, and text URL drops on the Dock icon.
Architecture
Posts
2026-04-29
App Notes: Web App Viewer