Starting with Mozilla Firefox version 13, Firefox has started to store your file download history in the history section. You can view your download history either from the menubar or by pressing the hotkey Ctrl + Shift + H and selecting the Downloads section in the left side list. This list shows all the files that you have downloaded from the internet. Just about anybody can see the files you downloaded by opening this window. But you can set Firefox to automatically clean your download history using an add-on called Download Cleaner.
The Download Cleaner add-on gives you option to automatically clean the downloaded files history immediately after the download is finished or when you close the Firefox browser. The option for disabling only the download history does not exist in Firefox. This is why Download Cleaner is a very useful Firefox add-on when you do not want to clean all the browser history, but just the downloaded files history.
You can download and install the Download Cleaner add-on from the Mozilla add-ons website. The installation of this add-on does not require you to restart the Firefox browser. The add-on does not show anywhere but keeps working in the background. In the settings for the addon, which you can open by pressing the hotkey Ctrl + Shift + A, you have options to clear downloads instantly or clear downloads on exiting Firefox.
The Download Cleaner is an add-on that works for very specific needs of some people who like to keep their download history clean. It can keep your download history clean without interfering your normal browsing of the internet and without changing your browsing history.
You can download and install Download Cleaner from https://addons.mozilla.org/.