It's hardly the only multifeatured download enhancement add-on in Firefox's deep add-ons catalog, but DownThemAll is one of the best. It just got better with an upgrade to version 2 that supports Firefox 4, can customize download speed limits, and sniffs out media including support for HTML5.
While support for Firefox 4 was essential to the add-on's continued life, the granular controls over download speeds are a welcome surprise. You can now set different maximum download speeds by individual download, by server, or as a global preference. Separately, you can also set download limits by server.
Firefox's trackless browsing option receives support in DownThemAll 2. This means that even if you're running in Private Browsing mode, you can run the add-on and get the increased download speeds it provides.
The media-sniffing option will discover and download audio and video embedded or linked in a Web page for you, as long as you're looking at a site on HTTP or HTTPS. Of course, this is the case for the vast majority of users and ought not to pose a problem.
DownThemAll's queue control has been improved as well, with new filters available to help clear the line of in-progress and completed downloads that have been set up; and DownThemAll now offers official, developer-sponsored integration with the Firefox add-on Video DownloadHelper. HTML5 support includes both and tags, at least as far as they've been documented and integrated into the browser itself. The HTML5 standards have yet to be finalized.
Other changes of interest to the add-on include better context menu integration; a rejiggering of how the average download speed gets calculated to favor more recent downloads; and support for third-party download services such as RapidShare without having to enable third-party cookies when cookies have been disabled. Some add-on defaults have been changed, too, including making five auto-retries spaced 5 minutes apart before marking a download a failure; upping the number of concurrent downloads from four to eight, although concurrent downloads from the same server remain restricted to four; and granting read permissions to the user group for new downloads.
Another change to DownThemAll comes from a savvy fan of the add-on who found that it works much better on Windows 7 when a Microsoft bug fix has been applied to the operating system, and so the add-on publisher recommends that Windows 7 users make sure they've installed the fix for more stable downloading.
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