Gtk.Windows.Forms.WebView2 1.4.2464.26239

Gtk.Windows.Forms.WebView2

The Windows engine behind System.Windows.Forms.WebBrowser in Gtk.Windows.Forms.

Reference the package and nothing else: a module initializer registers the backend with WebViewBackendFactory, above the WebKitGTK one, so WebBrowser picks it up on Windows.

<PackageReference Include="Gtk.Windows.Forms.WebView2" Version="..." />

Without this package a WebBrowser on Windows finds no engine — WebKitGTK 6.0 is a Linux and macOS library — and falls back to a placeholder that shows a message and reports every navigation as failed.

What you are accepting

Airspace. GTK 4 gives a window handle only to toplevel windows; every widget inside one is drawn, not hosted. The browser is therefore a child window of the form's handle, positioned over the area the control occupies. It paints above all GTK content in that window: overlapping widgets, popovers, menus, drop-downs and window opacity do not clip it. There is no fix short of compositing the page into a GTK texture, which costs a frame copy on every paint.

Stale reads. As with the WebKitGTK backend, HtmlDocument and HtmlElement read a cached snapshot of the page rather than the live DOM, and InvokeMember / InvokeScript post the call and return null. Both are recorded in the library's EMULATION-GAPS.md; Gtk.Windows.Extensions carries async siblings that do return values.

No incremental progress. WebView2 reports no load percentage, so ProgressChanged fires with 0 when a navigation starts and 100 when it completes, rather than counting up.

The runtime

The package needs the Microsoft Edge WebView2 Runtime, which ships with Windows 11 and with recent Edge installs. Check for it before you rely on it:

if (!WebView2Runtime.IsRuntimeAvailable)
{
    // WebBrowser will fall back to the placeholder.
}

Nothing is downloaded unasked. If your application is willing to fetch Microsoft's Evergreen bootstrapper on its users' machines, say so explicitly before the first WebBrowser is created:

WebView2Runtime.AllowRuntimeBootstrap = true;

That is an application's decision, not a library's, which is why the switch lives here rather than on System.Windows.Forms.WebBrowser — that type mirrors real WinForms, and additions belong in companion packages.

Licence

LGPL v3, the licence the vendored upstream carries. See LICENSE.txt in the package.