Earlier quoted context omitted.
Firefox exposes this stuff just fine: its context menu on videos has “View Video”, “Copy Video Location” and “Save Video As…”. (I thought that Chrome did too, but maybe my memory is faulty or maybe they removed it at some point.) But sites can easily prevent all of this stuff from happening by putting something transparent on top of the video, so that you’re not actually right clicking on the video, but on another el…
> Firefox exposes this stuff just fine: its context menu on videos has “View Video”, “Copy Video Location” and “Save Video As…”. (I thought that Chrome did too, but maybe my memory is faulty or maybe they removed it at some point.) You're right, I never noticed that. Although I just tried on youtube and the option are there... but greyed out. Not sure why. As for the various formats, if the web wasn't a javascript sh…
Switching between sources mid-play is a lot harder than most realise, because random seek is expensive in videos. So instead you tend to treat it as a large number of files of a few seconds each that get glued together as you play it, and you can switch between them as you go.
The web platform could be extended to cover multiple-bitrate streaming and let the browser take control, but that’s a pretty complex affair, and I suspect that it still wouldn’t be enough to make these operations work—the browser would need a way of putting it back together again into one file.