The following code fails for this particular host.
var request = WebRequest.CreateHttp("https://jira.sil.org"); /* doesn't work */
//var request = WebRequest.CreateHttp("https://www.google.com"); /* works */
var response = (HttpWebResponse)request.GetResponse();
> mcs tlstest.cs /r:System.dll /r:Mono.Security.dll
> mono tlstest.exe --web "https://jira.sil.org"
Error #-2146762487: CERT_E_UNTRUSTEDROOT 0x800B0109
although the certificates are installed with mozroots and the certificate of that host is valid.
No error shows when I leave out the "--web" parameter:
> mono tlstest.exe "https://jira.sil.org"
It doesn't work even when I explicitly import the certificates with:
> certmgr -ssl https://jira.sil.org
Debugging into it I see that mono calculates a different certificate chain from the certificate chain that Firefox shows.