Are you sure nothing happens? In the JS a checkbox is checked if checked (O_o), is it? Can't spot it on the screens.

All tutorials also say to save the server side certifcate as a *.p12 and use it in SSL Manager. But chrome only offers to me save the certificate in cer or p7 format - and even then I don't know the password for it.

Thank you for you answer. It is helpful even if I don't get it do work because I don't know which certificate the site is using. The certificate chrome shows me is a server-side cert, but I don't know which client cert my browser uses for this. Also I still don't understand why I can open the page without any ssh-problems (see step 4) but don't login (step 5) both using jmeter. Seems like I must try using Selenium which uses the browser itselfs and not trying to "programm" ist with jmeter, even selenium is not made for run 100 threads.