I am relatively new to mac and opera and can´t find a solution in google to my problem on os x but there are many instructions for windows and older opera versions.
The Problem is probably in the Opera Turbo Settings and there is the blue button next to the url bar but I can`t find how to disable it.
Mac OS X 10.11.3
sorry guys, found the settings on: http://www.filecritic.com/opera-34-with-improved-opera-turbo-data-saver-mode-released/
the setting is in the mac top bar on Opera -> Opera Turbo
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