It also means that the rendering will potentially be different on each platform given they all use different native webviews (and there's no "native" webview on Linux but WebKit-gtk is the most widely used one)
My hope is that something like Servo gets good enough to be included, especially if it's tree-shakable so you can only include a subset of the codebase. I don't know if that's a goal for either projects, but it would be cool - the default webviews can be quite lacking so currently you need to use a restricted set of HTML/CSS/JS to guarantee compatibility.