Read mp4 unfinished file

[jdr]

I am aware that the mp4 format contains information at the end of file, but so do most other video formats.
When I play a movie that is still downloading(any format but mp4),VLC asks me if I want to rebuild the index or play the broken file. Playing the file works but seeking is disabled as the index is unfinished.

Could you please implement this feature for mp4 files as well ?

Thank you.