How to accept self-signed SSL certificates with selenium firefox driver?

Question

I want to run some automated browser tests on my ASP.NET Core 2.1 web application. For this application, I have HttpsRedirection enabled, and I ran the command dotnet dev-certs https --trust to trust the ssl certificates used by ASP.NET Core.

I have downloaded the firefox selenium driver and added the executable to my PATH. This works as a firefox window is opened when I run the code.

Accepting the risk and continuing does nothing as the code has already disconnected from the browser.

var firefoxOptions = new FirefoxOptions();

var profile = new FirefoxProfile();
profile.AcceptUntrustedCertificates = true;

// Tried the following, got this: Invalid moz:firefoxOptions field acceptInsecureCerts
// firefoxOptions.AddAdditionalCapability(CapabilityType.AcceptInsecureCertificates, true);

firefoxOptions.Profile = profile;

var driver = new FirefoxDriver(firefoxOptions);
driver.Url = "http://localhost:5002/";

I expect to be taken to my web app, as happens when I browse to http://localhost:5002 in firefox myself. Instead, I get the following:

Answer 1

Set the parameter directly on FireFoxOptions instead of the profile...

var firefoxOptions = new FirefoxOptions();
firefoxOptions.AcceptInsecureCertificates = true;

I also noticed your URL is non https, if you want to be accepting an insecure certificate, you should probably browse to https instead, i.e

driver.Url = "https://localhost:5002/";