Let's refer to safe browsers like Avast Safe Zone, Bitdefender Safe Pay and all those browsing tools -generally included into the paid antivirus suites- which are supposed to protect users data from being stolen during payments within the e-commerce websites, and in general ensure high level of privacy and safeness while using unsafe devices (and even while connected to public networks as far as I remember).
If I understood correctly these safe browsers are based on HTTPS encryption and so I wonder if using the HTTPS protocol on standard browser might ensure the same level of safeness (e.g. by installing the "https-everywhere" add-on on Firefox). If not, which kind of key-protective-elements these special browsers are based on? Why are they supposed to be better than normal browsers which may have a suite of security extensions installed?
In other terms, are these antivirus safe browsers really more secure and how do they work?