Some web sites support both HTTP and HTTPS protocols. If you are unsure what they are, a brief explanation is that the HTTP is a network communication protocol that the web uses, and HTTPS is the combination of HTTP and SSL/TLS protocol (something for encrypted communication). In even simpler terms, HTTPS generally gives better data protection.

If you wish to force Chrome to open web sites in https protocol (provided that the web site supports it), apart from installing extensions, here is another method:

open chrome://net-internals/ in the address bar go to the HSTS tab under Add domain , enter the domain name which you want Chrome to always open with https protocol (for example, dropbox.com) check Include subdomains done!

If for some reasons you want to cancel this, scroll a bit down on the same page, find the Delete domain section, enter the domain name you want to remove from the https list and click Delete.

source +Andy WU, via Chromi