Browser.cache.memory.capacity May 2026
browser.cache.memory.capacity is a Mozilla-based browser (like Firefox, Thunderbird, or Pale Moon) preference that determines the maximum amount of Random Access Memory (RAM) dedicated to caching decoded images, script data, and other web content.
Positive Integer: A custom limit set in Kilobytes (KB). For example, entering 524288 would cap the memory cache at 512 MB. How to Modify It Open your browser and type about:config in the address bar. Search for browser.cache.memory.capacity. Double-click the entry and enter your desired value in KB. Browser.cache.memory.capacity
Double-click the value to edit it, or use the plus/pencil icon to create it if it doesn't exist. browser.cache.memory.enable for these changes to take effect. mozillaZine Related Configuration Tips Checking Current Usage browser
Part 3: Why Change browser.cache.memory.capacity?
There are three distinct profiles of users who might want to deviate from the -1 default. Decreasing the capacity :
Part 3: Why Change browser
