I don't dare to use this since Opera got bought by that Chinese consortium of companies I'm not accustomed with. Not sure if I'm overly cautious? I'm thinking of especially Opera Link (which had a recent security breach to boot!). Wouldn't that leave out my passwords to China? And I do want to use some sort of syncing, I'd go crazy without anything there or some iffy third party addon. It's not even just about a trus…
> 12. THIS CONTRACT IS BASED ON NORWEGIAN LAW. This EULA will be governed by the laws of Norway without giving effect to any conflicts of law principles that may require the application of the laws of a different country.
Other potentially interesting terms -- "components" from "third parties" may be delivered along with Opera. Operate claims they're not responsible for that software, despite making the choice to deliver it to you:
> 5. COMPONENTS FROM THIRD PARTIES MAY BE DELIVERED ALONG WITH THE SOFTWARE. The Software is delivered along with certain software components provide by third parties (“Third Party Software”). Opera shall not be responsible for any such Third-Party Software.
Opera may come with "additional services", including one that routes your browser traffic through an Opera proxy:
> 6. THE SOFTWARE MAY INCLUDE ADDITIONAL OPERA SERVICES. Various additional Opera services may be offered where available via or as integrated into the Software (“Services”). These Services may include one or more of the following:
> ii. Compression: The Software includes compression functionality to enable users to boost the download of web content such as webpages and/or videos. This functionality requests web content through Opera’s proxy or compression servers. Your browsing experience may change due to increased loading speeds.
This last clause seems to allow Opera to route your web traffic through their servers, where they presumably have the technical ability to examine, record, and modify it. It's not clear to me if the EULA places any restrictions on how they may interact with this traffic, to record it, examine it, etc.
Others of these "additional services" are described as "optional", whereas the compression service is not:
> v. Contextual Hints: The Software may include “Browser Assistant”, a component that provides contextual hints about certain Opera browser features and other useful information which you might be interested in. Browser Assistant is an optional component of the Software.
Though, to be fair: the third-party reference may be referring to open source software (but doesn't appear limited to that); and Opera's compression service is similar to features offered by other browsers like Google Chrome.