Click update and wait for the installation to finish. If no update button appears, you are already on the latest supported version for your firmware. Method 2: Sideloading the APK (For v6.17.730)

The ability to force higher bitrates or resolutions (like 4K) even if the official app limits them based on perceived bandwidth. SmartTubeNext:

In conclusion, the search for "Smart TV YouTube 617 391 download latest version extra quality updated" reflects a legitimate user demand for performance and control. While specific builds can indeed offer temporary benefits – faster startup, sharper video, less buffering – they are not a long-term solution. The most reliable way to enjoy "extra quality" YouTube on a Smart TV remains a combination of: a stable high-speed internet connection (50+ Mbps for 4K), a TV with hardware decoding for VP9 (for YouTube’s preferred codec), and patience with official updates. Sideloading is a powerful tool for advanced users, but for most, the official, automatically updated channel is the safer, more sustainable path to a premium viewing experience.