Maybe it’s something in UI, but many times I watch pictures (not even videos, they are their own can of worms), and want to save them, it shows me that I’m downloading them again although they are cached in whatever app I see them from.
Like this link with a happy dog: https://i.pinimg.com/736x/71/1e/52/711e52f1d6c7ead78f4380214f68c259.jpg
I see it in high rez in my browser, I can zoom in, and I can’t tell any difference from a copy that I can download, but it’s still, well, another download if I want to save it, and not a move from cache to my download folder, another request to the server, another waste of traffic.
Is there some rule of sandboxing for everything you load that I don’t know about? In cases like our fediverse, I wouldn’t like to cause double load when I already have the picture I want. Can I cut it down with some plugin in mobile Firefox?
I feel like I’m missing something big time.
Virtually everything that’s ever written permanently to disk first exists in memory though.
If the system isn’t built to move it from memory to the disk then it isn’t easy to just move it over. The browser might have the file stored in a way that makes it easy to stop and fastforward or even allow it to play or partially load,. Trying to save a file that might be incomplete is far more complicated than a good old reliable direct download.
Think of it like orange juice. The browser may have stored it in a wide shallow bowl because that works better for the browser, but it would be a pain in the ass to pour into a small cup. Much easier to just pour a new cup of orange juice when it is in an expected format.