Distribution of WebView2 user native NetForms App: is WebView2 Runtime really needed? - winforms

Question

Due to end if IE life, I am replacing the WebBrowser (IE based) control in our native .net forms app (c#) to Microsoft.Web.WebView2.WinForms.WebView2.
The distribution page says, the user needs to install the WebView2 Runtime, which is about 100 MB!
My question, is this really needed? Isn't it enough to have the MS Edge installed (which is on EVERY Windows 10 machine)?
This page says:
Prerequisites: Ensure you install the following list of pre-requisites before proceeding. WebView2 Runtime or any Microsoft Edge Insider (preview) Channel (Beta, Dev, or Canary) installed on a supported OS (currently Windows 10, Windows 8.1, and Windows 7).
However, I am not sure if Edge Insider is a normal user's Edge Browser?
So, do I really need to distribute 100MB WebView2 Runtime (some of our customers are offline users) together with my App Installer (which uses WinForms.WebView2 control to display HTML pages inside my native App), or it's enough if MS Edge is installed on those systems?

Answer 1

The answer is: Yes, you need to install the WebView2 Runtime! The version of Edge installed on user's machines is NOT insider channel - it's the Stable channel.
Although you can use the Edge Insider channel, this is is not recommended except for developing, since only developers has this version.
To quote the page you linked to: "Microsoft Edge Stable channel isn't supported for WebView2".

Answer 2

Yes, you really need to distribute WebView2 Runtime. From the doc you link, you can find the reasons:
Under this paragraph Runtime or browser support during development or production, you can find that:
A production release of a WebView2 app can only use the WebView2 Runtime as the backing web platform, not Microsoft Edge.
The pre-installed browser on Windows 10 is Edge Stable Channel, most people won't install Edge Insider (preview) Channel, and:
Microsoft Edge Stable channel isn't supported for WebView2

Answer 3

Yes, include the WebView2 runtime in your distribution kit.
If you include the WebView2 Evergreen Bootstrapper in your kit, it will fetch the latest evergreen embedded browser. It's intended to be future-proof even if you don't update your kit for a while.
My kit installs correctly on W10, W7SP1, W8.1, WS2016, and WS2019 when I include the <2MiB bootstrapper and run it.
And, your installer can detect whether WebView2 is already installed, and skip reinstalling it. I hope everybody writing an installer will do that. If we do, then our users will be spared a reinstallation for each new WebView2-using app.
This little Inno Setup code stanza detects it correctly for me. Returns True when it's necessary to run the WebView2 installer.
function WebView2IsNotInstalled: Boolean;
var Pv: String;
var key64: String;
var key32: String;
begin
key64 := 'SOFTWARE\WOW6432Node\Microsoft\EdgeUpdate\Clients\{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}';
key32 := 'SOFTWARE\Microsoft\EdgeUpdate\Clients\{F3017226-FE2A-4295-8BDF-00C3A9A7E4C5}';
Result := True;
if RegQueryStringValue(HKEY_LOCAL_MACHINE, key64, 'pv', Pv) then
begin
Result := 0 = Length(pV);
end
else begin
if RegQueryStringValue(HKEY_LOCAL_MACHINE, key32, 'pv', Pv) then
begin
Result := 0 = Length(pV);
end;
end;
end;
(Please doublecheck this code: I am not an installer whizz.)