Reduce Memory (RAM) usage in Firefox and Thunderbird Easily

Originally posted by Ryan at Cybernet: Now, this is by no means a REAL fix for the Firefox memory leak, but it certainly does appear to help it quite a bit. This little fix will move Firefox to your hard drive when you minimize it, and as a result it will take up less than 10MB of memory while minimized. So far, from my experiences with using this today, when you maximize Firefox it will obviously increase the memory usage. However, it does not seem to go back up to the insane amount that it was at before minimizing it. For example, Firefox was at 180MB of memory usage and then I minimized it and after a few seconds I maximized it. After maximizing it and continuing on my routine business it appeared to only have gone up to 60MB. This seems to be a good solution for me right now since I frequently maximize and minimize Firefox anyways. Now I know many people will say that Firefox will take longer to maximize since it will be located on the hard drive, but I haven’t noticed ANY delays. It is able to redraw itself just as quickly as if it was located in the ram (in my experience). Okay, now here are the few simple steps: Open Firefox and go to the Address Bar. Type in about:config and then press Enter. Right Click in the page and select New -> Boolean. In the box that pops up enter config.trim_on_minimize. Press Enter. Now select True and then press Enter. Restart Firefox. See how quick and painless that was? At any rate you can always go back and delete the same setting that you just created if you start to experience any issues. I have also set the browser.sessionhistory.max_total_viewers value to 0 because that will prevent Firefox from caching pages for the back button. This is also supposed to free up some memory that gets stolen. Update: Martin has informed me that this fix also works for Thunderbird. I am not a Thunderbird user so I didn’t realize this. After thinking about it I realized it “should” also work for Netscape, Mozilla, and SeaMonkey. Also, this fix is only for Windows machines (sorry Mac users).