Open Firefox, type about:config into the address bar, and press . Step 2: Accept the Warning
If the default -1 isn't working for you, try these manual caps: Your System RAM Recommended Cache Value (KB) Equivalent in MB/GB 15000 to 20000 4GB - 8GB 256000 to 512000 256 MB to 512 MB 16GB+ 1048576 or 2097152 1 GB to 2 GB
You are testing a progressive web app (PWA) or a single-page application (SPA). You need to ensure that a specific JavaScript file is always re-fetched from the network, not from a stale memory cache. Browser.cache.memory.capacity
Recommended for most users. Firefox dynamically calculates the size based on your total system RAM.
Capacity looked at Tab 1. It was an unfinished email. Vital. Open Firefox, type about:config into the address bar,
This preference dictates exactly how much of your computer’s RAM (Random Access Memory) Firefox is allowed to use for storing web content temporarily. Unlike disk-based caches that save assets to your hard drive or SSD, the memory cache is the elite, lightning-fast tier of storage. When configured correctly, it can make page reloads feel instantaneous. When left at its default—or configured incorrectly—it can lead to sluggish performance, excessive memory usage, or wasted resources.
To modify this setting in Firefox:
that determines how much system RAM (memory) the browser can use to store web pages, images, and scripts for instant retrieval. Unlike the disk cache, which stores files on your hard drive, the memory cache is significantly faster but is cleared every time you close the browser. 1. How to Access the Setting