The Evergreen Runtime does not come pre-installed on Windows 10 or early Windows 11 builds. (It is now inbox on Windows 11, version 23H2 and later, but not guaranteed on older OSes).
The solution: When your app launches, check for the runtime. If missing, download the Evergreen Bootstrapper (a 2MB executable) from Microsoft, which fetches and installs the latest runtime.
When a user installs the Microsoft Edge browser (stable channel), the Evergreen WebView2 runtime is automatically installed and shared across all apps on the machine. It lives in a well-known system folder (typically C:\Program Files (x86)\Microsoft\EdgeWebView\Application).
If a user does not have Edge installed? No problem. When your app installs, you call the simple Bootstrapper (a tiny 1.5MB executable) that downloads and installs the Evergreen runtime silently in the background.
The term "evergreen" in software refers to a product that updates itself automatically in the background, without user intervention or manual downloads. Your web browser, whether Chrome, Firefox, or Edge itself, is evergreen. It silently updates to the latest version, bringing new features, performance improvements, and—most importantly—security patches. evergreen webview2
Evergreen WebView2 applies the same philosophy to the runtime used by your application.
WebView2 offers two primary distribution modes:
| Feature | Evergreen | Fixed Version | |------------------------|------------------------------------|----------------------------------| | Runtime updates | Automatic (via Microsoft) | Manual (developer-controlled) | | App size overhead | None (shared runtime) | Large (runtime embedded) | | Security patches | Immediate (OS-level) | Developer must redistribute | | Chromium version | Latest stable (rolling) | Pinned at development time | | Network deployment | Simple (check for runtime presence)| Complex (include binaries) |
The Evergreen mode is the recommended default for most applications because it reduces the developer’s burden to ship security updates and ensures users always have a compliant, up-to-date web platform. The Evergreen Runtime does not come pre-installed on
Once upon a time in the bustling city of Windows, a developer named Alex was building a grand new application. Alex wanted a window that could show the magic of the web without carrying the weight of a whole browser in their suitcase.
Alex discovered a companion named Evergreen WebView2. Unlike the "Fixed Version" travelers who had to carry their own heavy tools everywhere they went, Evergreen was light on its feet. It shared a single, powerful engine already built into the city’s foundations—Windows 11. The Secret of Eternal Youth
The true power of Evergreen was its ability to stay young forever. While other apps grew old and vulnerable to the bugs of the world, Evergreen received mysterious packages from the Microsoft Edge Updater. These packages contained the latest security shields and web standard scrolls, keeping Alex's app safe and modern without Alex ever lifting a finger. The Great Balancing Act
But being Evergreen wasn't without its trials. Because it was always changing, Alex had to be a watchful guardian. They practiced the "Ancient Rites of Development": Evergreen webView2 runtime compatability issue? #2210 Once upon a time in the bustling city
await CoreWebView2Environment.CreateAsync( browserExecutableFolder: null, // null = use Evergreen system runtime userDataFolder: "C:\\AppData\\MyApp\\WebView2", options: new CoreWebView2EnvironmentOptions() );
// Check runtime availability string version = CoreWebView2Environment.GetAvailableBrowserVersionString(); if (version == null) // Launch bootstrapper from https://go.microsoft.com/fwlink/p/?LinkId=2124703 var installer = new WebView2RuntimeInstaller(); await installer.InstallEvergreenRuntimeAsync();
The Evergreen runtime is located automatically by the WebView2 loader.
In software development, "evergreen" means the software automatically updates itself in the background without user intervention. You don't download version 2.0; you just wake up one day and you are on version 2.0.
Chrome, Firefox, and Edge are evergreen browsers. The old Internet Explorer was not (it required OS-level patches).
Problem: Microsoft pushes Edge updates every 4 weeks. You cannot delay an update company-wide without enterprise Group Policies. Solution: In enterprise environments, IT admins can control Edge update policies. For individual app developers, you must accept Microsoft’s cadence.