Just FYI, opera was sold in 2016 to a consortium called Qihoo 360. Do your own research but there have been concerns raised in as to some of their operations, and i think many of the concerns about chrome now apply to opera as well.
> When you attempt to install other browsers, the 360 Safe Guards will allow the browser to be installed but will then popup saying not to let it become the default browser.
> When users of 360 Safe Guards run a check of their system, if they don't have the 360 browser installed it will give them a failing grade. If the user chooses another security software to protect their failing grade browser, the Safe Guards say no.
Also interesting is a statement by Opera on the 2016 acquisition [2]:
> The transaction would give Opera access to the extensive internet user base of Kunlun and Qihoo in China as well as the financing and other support of the Consortium that would allow for the full potential of the Company to be realized. At the same time, Kunlun and Qihoo would be able to cross-sell their products and services to the Opera user base, and benefit from Opera’s leading mobile advertising platform.
[1] https://web.archive.org/web/20150723081728/http://www.digita...
[2] https://arstechnica.com/information-technology/2016/02/chine... (can't find a direct link)