Rename preference: "downloadsMaxRetentionDays" -> *Hours
So, use hours instead of days + decrease default value to 3 days
(#5)
Correct shouldPersistDownload()
Probably bug in
http://mxr.mozilla.org/mozilla-central/source/toolkit/components/jsdownloads/src/DownloadIntegration.jsm#305
"shouldPersistDownload: function (aDownload)"
(#5)
Force save downloads.json, this may fix startup errors
(but only after restart...)
(#5)