src/vs/workbench/services/environment/browser/environmentService.ts/BrowserWorkbenchEnvironmentService/webviewExternalEndpoint
class BrowserWorkbenchEnvironmentService:	get webviewExternalEndpoint(): string {
		const endpoint = this.options.webviewEndpoint
			|| this.productService.webviewContentExternalBaseUrlTemplate
			|| 'https://{{uuid}}.vscode-cdn.net/{{quality}}/{{commit}}/out/vs/workbench/contrib/webview/browser/pre/';

		const webviewExternalEndpointCommit = this.payload?.get('webviewExternalEndpointCommit');
		return endpoint
			.replace('{{commit}}', webviewExternalEndpointCommit ?? this.productService.commit ?? 'ef65ac1ba57f57f2a3961bfe94aa20481caca4c6')
			.replace('{{quality}}', (webviewExternalEndpointCommit ? 'insider' : this.productService.quality) ?? 'insider');
	}