How to use HTTP(S) proxy in Opera browser
Opera is a well-known free browser which is very popular in Europe. Opera is a quick and powerful browser with features like sending and receiving e-mail messages, managing contacts, chatting on IRC, downloading files via BitTorrent, and reading web feeds and etc.
Using proxy in Opera is easy to configure:
Run Opera and click "Menu" then "Settings" then "Preferences"
Go to "Advanced" tab, click "Proxy Servers..."
Fill in IP addresses fields and Port fields also.
Feel free to enable Proxy Support with pressing F12 key and choosing Enable Proxy Servers in a quick way
Now you could enjoy serfing with Opera over HTTP proxy.