If you’ve been using Firefox since the old days, you may have noticed that in version 2 (Bon Echo), the downloads history list automatically clears itself. This is in contrast to the former behavior (say, in 1.5) where it retains the list. Now this became a performance issue since keeping a long list of downloaded items can hamper performance (one downside of Firefox is that it’s a resource hog).

Here are some ways to tweak this behavior.

Option 1 - The Easy Way

• You can simply access Tools -> Options
• In the Privacy tab check or uncheck “Remember what I last downloaded” option

Option 2 - The Expert Way

• Access the about:config page.
• Find the browser.download.manager.retention preference name
• Double-click on it and enter any of the following values:
• 0 - List clears upon download item completion
• 1 - List clears upon browser exit
• 2 - List clears only by clicking ‘Clean Up’ button
• The changes take effect instantly