Just a general rule of thumb that has served me well: If it's GPL, Apple wouldn't be using it. Apple hates the GPL as it is the antithesis of their operating model.

https://webkit.org/licensing-webkit/

WebKit is part LGPL, and part BSD.

So I think from purely a licensing point of view, they are probably not in violation. Provided that the way they are linking the LGPL-licensed code is compatible with the LGPL.

But like the other commenter said, I too would not run any web browser that was not fully open source, like this Orion browser.