Hey @jooize,
I had set the https server to request a client certificate for a first time visitor. However, you shouldn’t be continually asked to supply a client certificate.
So, I turned off the option in the https server where it requests a client certificate. The popups should be gone now. However, let me know if they still come up.
Cheers
P.S I never really looked into the benefit of having to request client certificates in the first place, simply because B&C Explorer doesn’t deal with sensitive client information.