Just upgraded to Firefox 30.0 and sessions no longer seem to work. The cookie just doesn't set.

Using $this->session->set_userdata()

Not using Firebug, although reading on the web indicated it has been a culprit with similar issues.

In case it's relevant,

$config['sess_cookie_name']     = 'dani_session';
$config['sess_expiration']      = 0;
$config['sess_expire_on_close'] = FALSE;
$config['sess_encrypt_cookie']  = TRUE;
$config['sess_use_database']    = FALSE;
$config['sess_table_name']      = 'ci_sessions';
$config['sess_match_ip']        = FALSE;
$config['sess_match_useragent'] = FALSE;
$config['sess_time_to_update']  = 300;

Firefox is accurately saving in a cookie the default session information (IP address, useragent, etc.) It simply won't add additional information to the session via set_userdata(). Not sure why :(

OK, I take all this back :) I got it to work somewhere else so I think something funky is going on.

OK, I take back my funkiness. Firefox sets the userdata, and then it gets destroyed right after somehow?? Works fine in older versions of FF, all versions of Chrome and Internet Explorer.

I got this fixed and it wasn't even a bug in the first place. Apparently upgrading Firefox corrupted DaniWeb's cookies. The cookies needed to be cleared to something fresh to work.