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I had partial downloads from a Private Browsing window, why have they disappeared?

  • 5 replies
  • 1 has this problem
  • 26 views
  • Last reply by cor-el

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Resulting from a failed download, I had several file pairs "XXX" (0 bytes) and "XXX.part" (several hundred megabytes), but it seems that Firefox silently removed these files when closing the private window. As I am told on the Private Browsing window start screen: "Firefox will save your: downloads" So I do not expect that Firefox tampers with my Downloads directory and destroys data in it! When downloads were marked "Paused", Firefox asked my whether I want to close the Private Browsing window, as the downloads would be cancelled, but when they were shown as "Failed" it did not say anything so it also should not modify anything!

(Note that the file pair is still valuable, even if it is no longer listed in any downloads list. https://support.mozilla.org/en-US/questions/1220917 describes how to resume a download and this method should also work for a private download.)

Resulting from a failed download, I had several file pairs "XXX" (0 bytes) and "XXX.part" (several hundred megabytes), but it seems that Firefox silently removed these files when closing the private window. As I am told on the Private Browsing window start screen: "Firefox will save your: downloads" So I do not expect that Firefox tampers with my Downloads directory and destroys data in it! When downloads were marked "Paused", Firefox asked my whether I want to close the Private Browsing window, as the downloads would be cancelled, but when they were shown as "Failed" it did not say anything so it also should not modify anything! (Note that the file pair is still valuable, even if it is no longer listed in any downloads list. https://support.mozilla.org/en-US/questions/1220917 describes how to resume a download and this method should also work for a private download.)

Modified by kede81

All Replies (5)

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PB will remove any cookies and site that is what it does to remove all traces. You should use the regular Browser for everyday usage instead. PB guarantee nothing stays should you close it out. Resume only works if the server side allows it or in the firefox has it listed in the download section. This when not using PB firefox. So you need to make a choice here on what you need to use.

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You wouldn't be able to resume an interrupted or failed download once you have closed all Private Browsing mode windows because this data is purged automatically, so keeping partial files on the hard drive wouldn't make sense (there is no history/download information available that can be used to resume the download).

You would have to save these part files yourself before closing PB mode and try to resume the downloads in a regular window (not sure if this works in PB mode) by starting a new download and pausing this download. While the download is paused you can replace the part files and resume the download.

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@WestEnd: you write "PB guarantee nothing stays should you close it out." this contradicts the explanation in the PB start screen, which says that bookmarks and downloads stay (which makes a lot of sense, this was data I have explicitly chosen to keep).

So still deleting downloads silently violates POLA (Principle of Least Astonishment). There may indeed be merit in removing the .part/0-byte file pair in case it happens to be useless and a user does not intend to go to the length of using the resume trick I already linked in my question. But if Firefox does that, I think the same popup which appears when there is a paused PB download should also appear when there is a failed PB download when PB is closed. That would alert me that I need to rescue the .part file if I want to keep it.

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Then you need to read more before using features you don't understand.

https://support.mozilla.org/en-US/kb/private-browsing-use-firefox-without-history

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Doesn't Firefox alert you that there are still active downloads that aren't finished when you close Firefox?

What Westend wrote about new bookmarks and finished download is right, but that likely doesn't apply to download that are still in progress like I wrote above.

You can try what I wrote in my above reply to see if that allows to resume a download. In PM mode you will have to save the files before closing Firefox.

  1. Move the old .part partial download and the final file without the .part that has size 0 to another location.
  2. Start a new download and pause it, don't close Firefox.
  3. Copy the two files (.part and 0 byte final) that you moved above back to the download location to replace the new files that were created.
  4. Resume the download in Firefox.