It is not blocked by DRM but different codec.
Even if you have two MP4 files, but if they were encoded differently ffmpeg will still need to do some computation to join them.
Gapless playback with MSE would require identical encoding, which is likely more prevalent in the Apple catalog than the wild west of Youtube. Client-side transcode would require DRM cooperation.
For two video streams with different encodings, swapping between two media players + prefetch can give a close approximation of a continuous video stream.
Gapless playback with MSE would require identical encoding, which is likely more prevalent in the Apple catalog than the wild west of Youtube. Client-side transcode would require DRM cooperation.
For two video streams with different encodings, swapping between two media players + prefetch can give a close approximation of a continuous video stream.