src/vs/platform/webview/electron-main/webviewProtocolProvider.ts/WebviewProtocolProvider/handleWebviewRequest
class WebviewProtocolProvider:	private handleWebviewRequest(
		request: Electron.ProtocolRequest,
		callback: (response: string | Electron.ProtocolResponse) => void
	) {
		try {
			const uri = URI.parse(request.url);
			const entry = WebviewProtocolProvider.validWebviewFilePaths.get(uri.path);
			if (typeof entry === 'string') {
				const relativeResourcePath = `vs/workbench/contrib/webview/browser/pre/${entry}`;
				const url = FileAccess.asFileUri(relativeResourcePath, require);
				return callback(decodeURIComponent(url.fsPath));
			} else {
				return callback({ error: -10 /* ACCESS_DENIED - https://cs.chromium.org/chromium/src/net/base/net_error_list.h?l=32 */ });
			}
		} catch {
			// noop
		}
		return callback({ error: -2 /* FAILED - https://cs.chromium.org/chromium/src/net/base/net_error_list.h?l=32 */ });
	}