I'm not sure what the hell is going on here but I can't access most of Bitcoin websites , website that I have tried so far are Blockchain.info , Coinmarketcap.com , BTC.com , Blocktrail.com , Poloniex.com , Kraken , Wirexapp , CoinsBank , Bitmixer.io and the list goes longer ...
Firefox keep giving me the following error : The connection has timed out , The server at Poloniex.com is taking too long to respond. (All websites)
And I will assume you can access bitcointalk.org since you just posted here, first of all try those sites on other browsers such as Google Chrome etc. If it loads on other websites then that's a Firefox problem.
https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-canFor me, if the site works on other sites but not Firefox, try to refresh Firefox at HELP tab and see how it goes.