I was trying to download the certificate for a WPA2-Enterpise network I was connecting to. However, when I clicked on the link to install it, the browser said the cert was already installed as a CA. This being a certificate to identify wifi networks, why is it being trusted by the browser for https connection? Also, I have never opted to trust this certificate for http-TLS connections before on this machine, which is why I found it strange that the browser was trusting it to begin with. The browser is Firefox.
The story makes sense up to the point you mentioned Firefox. Certificates are shared between applications by the operating system, this is the case for both Linux and Windows. Firefox has its own certificate store, because they have their vision to what is trusted and not. However Firefox can be configured to trust the OS shipped certificates as well. This would make sense since you have to install the certificate in order to connect to a network. Firefox then accepted the HTTPS because it was already present in the OS.