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Preserve Download Modification Timestamp


When Firefox downloads a file, it sets the file modification time to be the current time. This is pretty much how every browser behaves. However, some will point out that this behavior is actually wrong (though it's a matter of opinion).

This extension allows Firefox to preserve the modification time, that is sent by the server, when you download a file. This should work for any file downloaded via http://, file://, or ftp:// (Firefox 4.0+ and SeaMonkey 2.1+) so long as the server sends the proper information.

Known Issues
  1. Not a bug. Ignores files downloaded by Save Page As "Web Page, complete". Doing this uses a different mechanism.
  2. Mozilla bug. (Firefox <= 4.0.x, SeaMonkey?) If you click on a link to start a download, and the download finishes before you choose where to save it, the required server information is discarded before this extension is notified you downloaded a file (details here). To work around the problem, use the following methods to start a download:
  3. The first time the SeaMonkey "download" preferences dialog is opened after installing PDMTS, the "Preserve file modification times when possible" check box does not have the correct state. However, toggling the check box will change the preference correctly. After closing and opening the dialog, or restarting SeaMonkey, the check box will show the correct state.
If you're having problems, be sure to check the Error Console to see what's going on. To see more information in the error console, change the log verbosity to "Info" or "Debug" in the extension preferences.


Check out the code! PDMTS is now on GitHub:

Want to provide a translation? Status-4-Evar can be found on BabelZilla:

Please do not email me for support/help/bug reports. I will not respond and will probably just delete it. The preferred way to contact me is to post in the official support topic on MozillaZine or create an issue on GitHub.

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