Vivaldi ships with a load of preselected bookmarks. Mainly big news sites and some online stores. It seems like there is some affiliate marketing going on there. Some of these bookmarks link to a vivaldi.com page that redirects you to a siteplug.com page which again redirects you to the actual page.

Example bookmark: AliExpress -> https://vivaldi.com/bk/aliexpresscom-us -> http://ww2.siteplug.com/fly?${tracking params} -> https://best.aliexpress.com/?${more tracking params}

Siteplug seems to be the service with they use to monetize the traffic. Notice that the redirect link doesn't offer a https version. Neither does their website [0] that also just shows me a dead bird on most pages [1].

[0]: http://siteplug.com [1]: http://siteplug.com/for-partners

Re: "Why we are doing this", see https://vivaldi.com/company/

From wiki: > "Vivaldi began as a virtual community website that replaced My Opera, which was shut down by Opera Software in March 2014.[15] Jon Stephenson von Tetzchner was angered by this decision because he believed that this community helped make the Opera web browser what it was. Tetzchner then launched the Vivaldi Community—a virtual community focused on providing registered users with a discussion forum, blogging service, and numerous other practical web services—to make up for My Opera's closure. Later, on January 27, 2015, Vivaldi Technologies launched—with the community in mind[16]—the first technical preview of the Vivaldi web browser."

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As for income, it's the standard browser model – partnerships with default search engines and bookmarks.

Well you could always turn to an encyclopaedia.

* https://en.wikipedia.org/wiki/Vivaldi_(web_browser)#History