The frameborder attribute on the iframe element is obsolete

Author: spk

en/news/_posts/2013-01-23-confoo-with-ruby-in-montreal.md

@@ -19,7 +19,7 @@ quite impressive.
 They also have hands-on training and a hackaton in the two days before
 the main event.
 
-<iframe width="420" height="236" src="http://www.youtube.com/embed/86VcHcaurRQ" frameborder="0" allowfullscreen=""></iframe>
+<iframe width="420" height="236" src="//www.youtube.com/embed/86VcHcaurRQ" allowfullscreen></iframe>
 
 The event is at the Hilton Bonaventure Montreal, from February 27th to
 March 1st. [Tickets are sold online][2].

id/news/_posts/2013-01-23-confoo-with-ruby-in-montreal.md

@@ -18,7 +18,7 @@ mengesankan.
 
 Mereka juga mengadakan pelatihan dan hackathon dua hari sebelum acara utamanya.
 
-<iframe width="420" height="236" src="http://www.youtube.com/embed/86VcHcaurRQ" frameborder="0" allowfullscreen=""></iframe>
+<iframe width="420" height="236" src="//www.youtube.com/embed/86VcHcaurRQ" allowfullscreen></iframe>
 
 Acaranya diselenggarakan di Hilton Bonaventure Montreal, 27 Februari -
 1 Maret. [Tiket dijual online][2].

it/news/_posts/2013-01-27-confoo-with-ruby-in-montreal.md

@@ -19,7 +19,7 @@ argomenti. Il [programma][1] è impressionante.
 Ci saranno anche corsi interattivi e una hackaton nei due giorni prima
 dell\'evento.
 
-<iframe width="420" height="236" src="http://www.youtube.com/embed/86VcHcaurRQ" frameborder="0" allowfullscreen=""></iframe>
+<iframe width="420" height="236" src="//www.youtube.com/embed/86VcHcaurRQ" allowfullscreen></iframe>
 
 Questo evento è all\'Hilton Bonaventure Montreal, dal 27 febbraio al 1
 marzo. [I biglietti sono disponibili online][2].

ru/news/_posts/2013-01-23-confoo-with-ruby-in-montreal.md

@@ -19,7 +19,7 @@ e-Commerce, Security, Mobile, UX и другие топики. [Расписан
 
 Также там будут тренинги и хакатон за два дня перед главным событием.
 
-<iframe width="420" height="236" src="http://www.youtube.com/embed/86VcHcaurRQ" frameborder="0" allowfullscreen=""></iframe>
+<iframe width="420" height="236" src="//www.youtube.com/embed/86VcHcaurRQ" allowfullscreen></iframe>
 
 Событие пройдет в отеле Hilton Bonaventure Montreal, с 27-го февраля по
 1-е марта. [Билеты продаются онлайн][2].

stylesheets/main.css

@@ -166,6 +166,10 @@ pre code {
           border-radius: 0;
 }
 
+iframe {
+  border: none;
+}
+
 /* Layout  */
 
 .container {