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How to disable Firefox cache?

  • 7 replies
  • 12 have this problem
  • 314 views
  • Last reply by user1251572

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In the past in order to properly disable Firefox's cache I would set 'network.http.use-cache' in about:config, however now the option seems to have been removed, or at least its name seems to have changed as I can't find anything under that any more on the latest version of Firefox. So on the latest version (currently 46.0.1) how can one properly disable the cache?

In the past in order to properly disable Firefox's cache I would set 'network.http.use-cache' in about:config, however now the option seems to have been removed, or at least its name seems to have changed as I can't find anything under that any more on the latest version of Firefox. So on the latest version (currently 46.0.1) how can one properly disable the cache?

Chosen solution

The disk cache is used in normal (non PB mode) and stores persistent data on the hard drive. The memory cache in used in normal mode and in PB mode and is purged when you close Firefox. It is best not to disable the memory cache to avoid performance issues (Firefox needs some kind of cache to work properly).

What specific reasons do you have to disable the cache?

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All Replies (7)

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See:

  • bug 1198387 - Setting the network.http.use-cache pref to false breaks fetch interception

Please do not comment in bug reports
https://bugzilla.mozilla.org/page.cgi?id=etiquette.html


There are browser.cache.*enable prefs like these:

  • browser.cache.disk.enable
  • browser.cache.memory.enable
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cor-el said

There are browser.cache.*enable prefs like these:
  • browser.cache.disk.enable
  • browser.cache.memory.enable

There are, but what exactly do they do and which one do I need (if it either of those two)? What is the difference between them?

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Chosen Solution

The disk cache is used in normal (non PB mode) and stores persistent data on the hard drive. The memory cache in used in normal mode and in PB mode and is purged when you close Firefox. It is best not to disable the memory cache to avoid performance issues (Firefox needs some kind of cache to work properly).

What specific reasons do you have to disable the cache?

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cor-el said

The disk cache is used in normal (non PB mode) and stores persistent data on the hard drive. The memory cache in used in normal mode and in PB mode and is purged when you close Firefox. It is best not to disable the memory cache to avoid performance issues (Firefox needs some kind of cache to work properly). What specific reasons do you have to disable the cache?

Right, so it is the disk cache that I need to disable and that is now the option for disabling the cache? Also, sorry for my ignorance, but what does "PB" stand for?

The specific reason why I wish to disable the cache is security, I have had far too many malicious scripts coming with images and hiding in my cache causing me trouble, so if I am going to get any malicious scripts with my images or anything like that I want to be able just to restart my browser in order to clear it from memory and everything so I don't want a persistent cache. I have also not noticed any performance issue when disabling it so it helps me in terms of security, and doesn't seem to cause any issues.

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PB = Private Browsing mode

I think that the HTTP cache included some cases than the disk and memory cache, but I'm not an expert on this as Firefox has a lot of caches for all kind of data.

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cor-el said

I think that the HTTP cache included some cases than the disk and memory cache, but I'm not an expert on this as Firefox has a lot of caches for all kind of data.

Right, so if I just disable the disk cache will that be enough to stop it having a persistent cache of anything after I restart Firefox?

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The option that was removed, how was it different from the disk cache option?