Waterfox uses up too much of my memory. On average it uses 2gb of ram once I've had it open for a while, no matter how many tabs are open. Sometimes it goes up to 3gb of ram and then starts eating away at CPU resources too. Also, when I close the program it takes a long time for it to release the memory and the memory usage goes up before it goes down. It can sometimes take 5min before the program disappears from task manager. I'm hoping someone can give me some pointers on how to fix this.

Windows 7 64-bit

Waterfox 40.0.2

Add-ons: Adblock Plus, Bookmarks Checker, FlashVideo Downloader, Ghostery, Greasemonkey, HTTPS-Everywhere, Imgur Uploader, MD5 Reborned Hasher, Moxbar, My Weekly Browsing, Pearl Crescent Page Saver, RES, Search by Image for Google, Session Manager, Tab Counter, Thumbnail Zoom Plus, Xmarks