The roads I take...

The culmination of a long stream of work has just happened: The switch to the toolkit download manager has just landed on comm-central, along with the reworked tree-based download manager UI and the rewritten per-download progress windows (which formally aren't "dialogs" any more).



This is a rather large change code-wise: hg diff -r qparent -r qtip | diffstat before doing the actual qfinish and push told me that all those patches result in:
53 files changed, 5766 insertions(+), 620 deletions(-).

Most of the new code is the manager and progress UIs as well as the tests, the actual switch patch removes more than it adds due to obsoleting pref-applications-edit.xul, which the old file handling dialog needed to save the "remember this decision" checkbox info (yes, an evil hack).
Once we come around to remove the code we actually obsoleted in the mozilla-{central,1.9.1} tree, the deletions of that work will probably outweigh the current insertions of code lines overall - some of the obsoleted code might even still be packaged but not used by toolkit (and therefore, even Firefox).

Thanks to Justin (Callek) for figuring out how to do this all and taking on the work to make the actual backend switch (really work), thanks to Frank (mcsmurf) for fixing all the review comments to the actual switch patch while Justin is mostly absent due to being busy with work and family and not having a useful Internet connection around - and thanks to Neil for all the reviews.
Thanks for MDC and MXR and whoever wrote up useful in-code description of the tree interfaces that are not documented usefully on MDC yet, thanks to those who made it able that dropping in a custom UI to work with the toolkit download manager works at all.
And thanks for all the people who have been patiently waiting for this to happen - including the localizers who couldn't have fully working localized builds - up to now.

And here's what this means for you:

• If you are a SeaMonkey user, you will see a reworked download manager appearing in any 2.x builds from now on, starting with tomorrow's (!) nightlies, and 2.0 Beta 1. This implementation can resume downloads (even across sessions), search in your performed or ongoing downloads, clear the list of completed downloads through "Clear Private Data" and store more download history without making SeaMonkey startup time longer, among other things.
• If you are a localizer, you will see the localized builds working fully (and can advertise them to your testing community), including the download manager, also starting with those nightlies and (pre)release.
• If you are a Mozilla or extension developer, you can count on SeaMonkey supporting/using the full toolkit download manager backend from now on.

There surely are a number of things to improve in the UI still, a number of which are filed as dependent bugs of the download manager and progress UI bugs linked above. We are in a state though where we feel we are ready for putting what we have into the upcoming SeaMonkey 2.0 Beta 1.
Let us know how well it works for you and what we still can improve, both the backend and the UI code we have now (hey, even I understand the latter!) are a much better base to build those developments upon than the old xpfe code we had been using so far - you might even be able to work on it yourself!