So, when you finish your download, what is the result?
Did you download only one file or several?
Skimming Coursera’s Development pages, I see only website framework info for creating login and student grading… I see nothing else. That, in combination with their Partner statement suggests that their partners are responsible for setting up the actual videos which might be delivered any way using any technology.
So, there may not be any single standard way videos are served to you, Partners may each have their own idea what the video(s) may be.
I’d also say it’s likely that particular course video you’re describing is encoded with multi-streams for different bandwidths in a single file (For example, Microsoft streaming video can be encoded this way) or multiple files (YouTube encodes and serves video this way).
IMO less likely, there might be some kind of odd encryption, although encryption by itself shouldn’t enlarge a file that much… But maybe someone could embed massive padding although again I don’t think it’s very logical.
One way to at least analyze and perhaps download only a specific stream if multiple are offered is to try using JDownloader. When I point that to a YouTube video for example, all streams are identified and I can choose which one I want.
They have indicated that it is perhaps Opensuse issue - despite that i am certain that Opensuse use the standard Firefox - currently at v45.
We have narrowed the issue to right hand mouse button clicking the download button. If you click the download button - then the video is displayed in the tab, states it is corrupt, but you can still download and this DOES NOT cause the excessive bandwidth.
All videos are MP4 - no ability to choose a different coding etc.
I am using wireshark - no issues of encryption problems or repeated packets etc.
Chrome works ok - no issues.
As such, since Mozilla have indicated it may be Opensuse deployment of Firefox - will Opensuse investigate if the version provided by their repositories is different to the standard version available from the Mozilla web site ?.
If Opensuse can confirm that it is a standard version - then i can pass back to Mozilla.
Maybe this site uses some kind of prefetching. You could play with the corresponding options in about:config, like
network.prefetch-next or network.http.speculative-parallel-limit.
if the Mozilla people are passing the ball to openSUSE you can try a static build from Mozilla https://ftp.mozilla.org/pub/firefox/releases/46.0/linux-x86_64/
how are you downloading the video’s is there a download link or are you using a video leaching addon, some sites don’t allow resume and multi-segments the addon you might be using could be creating multiple requests and downloading multiple copies of said file.
I have not yet installed from Mozilla rpm - they have suggested this also.
One question - when i install - i assume this will overwite the existing - so i could go to the latest release and wait for Opensuse to cath up ?
As above, the instant i access the page with the video embeddede and displayed - i pause the video, and still, 50MB has been downloaded without any other interaction, for a 11.5MB MP4 file.
I am definitely downloading the entire file - which is being cahced - as when i then download specifically - no download from the internet, but the file is saved where i wish to place it - so it is a cache issue.
it’s not an rpm the mozilla people do not provide rpm’s it’s a bzipped tar archive you just use ark (or file roller) to unpack it somewhere (in dolphin you can right-click and chose unpack here) and click on the firefox icon, or in a terminal execute ./run-mozilla.sh
this version will use your existing firefox profile (your bookmarks and addons), you can not have both versions running at the same time but it will not replace or interfere with opensuse’s firefox.
Another thing to try is a new user (or a new firefox) profile as a bad addon or a preference might be causing your issues.
Thanks - i downloaded the full version 46 of Firefox and installed when as another user - ran as stated by Mozilla help file - and confirmed that version 46 has the same issue on my machineas per the package installed v45 - excessive downloads.
I am not sure if this would have been picked up by others if you are not looking for it. The download indicator states the file size correctly, but Wireshark has the correct download size. MOst people may not realise this is an issue.
Only occurs with Firefox and Coursersa and EdX download. Both organisations are served by Cloudfront.net.
good that you picked it up, personally I don’t check how much I’ve downloaded as I’m on a flat plan, but people with wireless access or caped traffic should keep an eye on their usage.