Puppeteer Sharp - Scarping

ScrapePage.cs

private async Task<DtoEst> LoadEinkommenssteuerAsync()
{
	await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);

	DtoEst dto = new DtoEst();
	var url = "https://www.bmf-steuerrechner.de/ekst/eingabeformekst.xhtml";

	#region SELECTORS
	// https://stackoverflow.com/questions/45110893/select-elements-by-attributes-with-colon
	// use css escapes: https://mothereff.in/css-escapes
	string id_checkbox_IsMarried = "bmf_form_ekst:ekst_pv:0";
	string id_input_Umsatz = "bmf_form_ekst:ekst_zve";
	string id_button_Submit2 = @"#bmf_form_ekst\3A income_ekst";
	#endregion

	//// This statement downloads and installs chromium
	//await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);
	var browser = await Puppeteer.LaunchAsync(new LaunchOptions
	{
		Headless = true
	});

	using (var page = await browser.NewPageAsync())
	{
    // load page
		await page.GoToAsync(url);
    // wait for element to be there
		await page.WaitForExpressionAsync($"document.getElementById('{id_input_Umsatz}')!=null");
		await page.EvaluateExpressionAsync($"document.getElementById('{id_input_Umsatz}').value = '{NettoUmsatz}';");
    // get element value
		var val = await page.EvaluateFunctionAsync<string>($"()=>document.getElementById('{id_input_Umsatz}').value");
    // wait for element to be there
		await page.WaitForExpressionAsync($"document.getElementById('{id_checkbox_IsMarried}')!=null");
		await page.EvaluateExpressionAsync($"document.getElementById('{id_checkbox_IsMarried}').checked = true;");

		await page.ClickAsync(id_button_Submit2);
    // wait for redirect
		await page.WaitForNavigationAsync();
    // get value from element
		var strValueEst = await page.EvaluateFunctionAsync<string>("()=>document.querySelector('#ui-id-4 > div.ekst_ergebnis > div:nth-child(6) > table > tbody > tr:nth-child(3) > td:nth-child(2) > strong').textContent");
		 // get value from element
    var strValueEstPercent = await page.EvaluateFunctionAsync<string>("()=>document.querySelector('#ui-id-4 > div.ekst_ergebnis > div:nth-child(6) > table > tbody > tr:nth-child(3) > td:nth-child(3) > strong').textContent");

		var deDE = new CultureInfo("de-DE");

		Decimal.TryParse(strValueEst.TrimEnd(" Euro".ToCharArray()), NumberStyles.AllowThousands | NumberStyles.AllowDecimalPoint, deDE, out var decValueEst);
		Decimal.TryParse(strValueEstPercent.TrimEnd(" %".ToCharArray()), NumberStyles.AllowThousands | NumberStyles.AllowDecimalPoint, deDE, out var decValueEstPercent);

		dto.EstBetrag = decValueEst;
		dto.EstProzentsatz = decValueEstPercent;
	}

	return await Task.FromResult(dto);
}