Important: Starting August 5th 2025, Appstore app submissions must be built using Kepler SDK v0.20 or newer, or the submission will be rejected.
This release has no updates to the installed SDK itself, but there are many OS level improvements and bug fixes. Key improvements include:
- Streaming playback: Improvements include fixes for video scaling, AV stutters, HDMI switching, and Shaka Player compatibility across multiple streaming apps.
- System stability: Improvements include resolving memory leaks, app crashes, and performance degradation during extended viewing sessions and channel switching.
- Interface reliability: Improvements include fixes for navigation issues, subtitle display, content preview screens, and app peek functionality.
This release requires OS 1.1 (201010441850) on your Kepler Fire TV Stick, which is compatible with the Kepler SDK v0.20. You can check your device software version by navigating to My Fire TV > About.
To validate, run kepler -v and you should expect that version 0.20.3719 is returned.
OS improvements and bug fixes
- Added customer-friendly OS update messaging in App Detail Page when app incompatibility occurs from missing device modules.
- Fixed app unresponsiveness issue on clicking the app peek’s Continue Watching row content tiles for media playback.
- Fixed video playback scaling issue where 2x resolution failed to display top-left quarter view while maintaining correct audio and playback functionality.
- Fixed streaming performance degradation problem caused by audio and video stutters in live sports content due to the track buffer reader blocking write operations in the media player stack.
- Fixed non-functional back button navigation from Program Detail page when accessed through Live Guide for streaming apps.
- Fixed app becoming unresponsive with black screen after HDMI source switching, followed by Application Not Responding (ANR) crash when returning to Home screen.
- Fixed ANR crash during live stream channel switching due to JS thread blocking. This was resolved through media track reconfiguration optimization and Shaka player patches.
- Fixed Shaka Player 4.8.5 playback failure (error 6002) during transition from unencrypted preroll to encrypted content periods in Dynamic Adaptive Streaming over HTTP (DASH) Video On Demand (VOD) content.
- Fixed app background crashes that occurred during HDMI source switching while video content was playing or paused.
- Fixed app randomly exiting to home screen during movie playback, requiring device reset to resolve playback stability.
- Fixed subtitle display cropping issues during VOD content playback across all streaming sessions.
- Fixed memory leak issue that caused app performance degradation and crashes during extended usage and channel switching, previously triggered by unreleased render targets and media player objects.
- Fixed video playback flickering when displaying progress seek bar with Screen Magnifier enabled in an app at 720p 60Hz resolution.
- Fixed inconsistent audio device hot-plugging behavior which caused playback error and unexpected launcher redirects during external audio device connection or disconnection.
- Fixed display scaling issue which caused half-screen visibility when switching between HDMI ports during device setup.
- Fixed app stability issue which caused crashes during extended viewing sessions without generating ACR logs.
- Fixed Electronic Program Guide (EPG) future program selection which displayed a gray screen instead of the Program Details page due to undefined airing start time in the app.