One of the areas that gets most cramped in Firefox is the download manager – especially if you, like me, download hundreds of new files a week. And an overcrowded download list renders the manager completely useless, despite the new features introduced in Firefox 3.
One quick way to solve this bottleneck is using the browser’s built-in cleaning tools, which you can configure to clean up certain areas automatically every time you close Firefox. It’s as easy as going to Options > Privacy and check the option that says “Always clear my private data when I close Firefox“.
However, as there may be some elements you don’t want to get rid off (such as saved passwords, cookies and the likes), you can click on the Settings button and select exactly the elements you want Firefox to erase – in this case, Download History would be enough.