If you’re constantly changing folders for downloading files in Firefox, then you might want to try out FavLoc. It allows easy set up for adding multiple “favorite locations” so that you can easily choose them when downloading a file. It then adds these locations to the File menu, the right click menu, and the download window.

There are many options that you can mess around with, including the options for which menus you want FavLoc to appear on. It is by default enabled in the image context menu, link context menu, file menu, and download prompt. Adding folders to your menu is easy, just add the folder and give it a name.

Alternative:

DownThemAll - This is my favorite download manager for Firefox. I really hadn’t known how great it was until recently. When you use this to save files to different locations, it will save the locations so that you can easily select them again later. However, it doesn’t really seem that you have control over the locations. I think it will only save a specified amount of locations, but I don’t think you can delete locations from the menu. If you do however use the same locations over and over again, then they should be in the list for easy access consistently. I would like to see FavLoc add support for DownThemAll, or maybe even see DownThemAll add an option like FavLoc to their addon.

Via Ghacks.