The company says with the 4.20 update (actually released last month), the browser now "allows users to surf the web and enjoy videos and photos on a large, virtual screen, just as if [they] were at the theater," according to the blog post. It also supports 180 degree streaming video on the web, making it easier to view 3D VR videos from YouTube, for instance.
You can also set a 360 degree background image from one supplied by a cloud graphics company called OTOY. That, along with the "Skybox" feature (which lets websites set their own 360 background images), adds a stronger VR element to web browsing.
Samsung integrated its file browser in the Gear VR, making it easier to find and open movies and other content, aided by voice control and the on-screen keyboard, which now supports 11 languages. Intriguingly, Samsung also introduced Bluetooth capability to the browser, including support for the Gear S3 smartwatch. It didn't specify what you could do with it, but hopefully it'll give you a bit more control over content or games than just using the touchpad, on-screen keyboard or optional gamepad.