Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox dropping sessions - running out of space?

  • 7 replies
  • 1 has this problem
  • Last reply by cor-el

more options

This has been going on for a few months, but I have a strange bug where Firefox will start instantly closing sessions. If I clear my cookies it will fix the issue temporarily, but a couple days later it will come back. It's almost like it's running out of space in one of my local .sqlite caches. I've particularly noticed that this happens for a specific domain where I regularly access lots of subdomains (100+ subdomains of a single domain) - it might be coincidental, but I thought that there might be some single-domain cookie storage limit, but from what I've read that limit should be very large and none of the stored cookies are very large and I don't seem to be having this issue in Chrome which - as far as I can tell - has the same single-domain cookie storage limit. Is there a limit to the number of cookies that it will store for a single domain (across subdomains)? Any insight would be much appreciated!

All Replies (7)

more options

The only limit I know of is the space on the hard drive. How much is there?

On the site with the issue;

Remove History For One Site

Open the History Manager <Control><Shift> H. In the search bar, enter the name of the site. Right-click on one of the listings and select Forget About This Site. This should remove all information, including any passwords / settings.

more options

Thanks Fred. The disk still has 30+GB on it, so I don't think that's it :)

And that trick only seems to work for a single subdomain, so it's not probably a good long-term fix. Any other thoughts? Thanks!

more options

Remove History should remove everything for the selected site. Note: Including bookmarks, passwords . . . . .

more options

Yeah, I've tried that (clearing everything from history) and it bought be a couple of weeks, but the problem comes back :(

more options

I called for more help.

more options

Awesome. Thanks Fred! I appreciate the help - hopefully we can get this resolved :)

more options

There are some limits for the cookies (MaxCookiesPerHost defaults to 150).

See the source code.

// default limits for the cookie list. these can be tuned by the
// network.cookie.maxNumber and network.cookie.maxPerHost prefs respectively.
static const uint32_t kMaxNumberOfCookies = 3000;
static const uint32_t kMaxCookiesPerHost  = 150;
static const uint32_t kMaxBytesPerCookie  = 4096;
static const uint32_t kMaxBytesPerPath    = 1024;

You can override these limits by creating a new Integer pref on the about:config page as listed further down in the page code. These prefs do not exist by default.

// pref string constants
static const char kPrefCookieBehavior[]       = "network.cookie.cookieBehavior";
static const char kPrefMaxNumberOfCookies[]   = "network.cookie.maxNumber";
static const char kPrefMaxCookiesPerHost[]    = "network.cookie.maxPerHost";
static const char kPrefCookiePurgeAge[]       = "network.cookie.purgeAge";
static const char kPrefThirdPartySession[]    = "network.cookie.thirdparty.sessionOnly";
static const char kCookieLeaveSecurityAlone[] = "network.cookie.leave-secure-alone";

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.