TYPO3 Core

This issue occurs when serving video files from a non publicly accessible FileStorage.
\TYPO3\CMS\Core\Resource\ResourceStorage::getPublicUrl() will generate an URL like this:

/index.php?eID=dumpFile&t=f&f=11623&token=047550942c914f1c4e4ae8d22a0bc2102661019b

When serving video files via a publicly accessible FileStorage the FAL can use "normal" URL, e.g.:

/fileadmin/user_upload/videos/awesome.mp4

iOS devices will check if the server supports byte-range requests when downloading/streaming video files, please have look into the documentation:
https://developer.apple.com/library/archive/documentation/AppleApplications/Reference/SafariWebContent/CreatingVideoforSafarioniPhone/CreatingVideoforSafarioniPhone.html#//apple_ref/doc/uid/TP40006514-SW6

Normal Web-Servers (like Apache and nginx) usually don't have any issues with byte-range requests.
Unfortunately the FAL can't handle byte-range requests.

I'll suggest that this feature/bug will be handled in \TYPO3\CMS\Core\Resource\ResourceStorage::dumpFileContents().
I'm not sure if this is the proper place for that.

I could reconstruct this issue in TYPO3 CMS 8 and 9 (other versions haven't been tested yet).