• Added full support for MKV S_HDMV/PGS subtitle tracks.
• Added PGS detection, menu integration, selection, and preselection.
• Preserved language, name, default, and forced metadata.
• Implemented PGS extraction using HTTP Range requests and CueRelativePosition.
• Reconstructed SUP windows with correct PGS timestamps.
• Added recovery of the previous epoch start / acquisition point during seeking and mid-stream playback starts.
• Added PGS decoding through PgsParser from libbitsub.
• Added canvas rendering for multiple PGS compositions with coordinates, alpha transparency, and scaling.
• Added handling for clear/end-display, seeking, OFF, track switching, and cleanup.
• Added cancellation of obsolete extraction requests during rapid seeking.
• Eliminated HTTP 429 errors caused by concurrent PGS window requests.
• Improved Luna service error propagation.
• Preserved the Cluster-based fallback for files without CueRelativePosition.
• Preserved full VobSub compatibility.