For Firefox, you can combine a Greasemonkey script (that obviously requires Greasemonkey) with DownThemAll, probably the best download manager add-on. After installing the two add-ons, restarting the browser and adding the script, go to the album you want to download, click on the "Init Download Links" button from the top of the page, select DownThemAll/DownThemAll in the contextual menu and type "imgdl=1" in the Additional filters box.
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