Browsers (esp Firefox), cookies, 'DOM storage', browsing history and privacy

[muriel_volestrangler]

I was trying to work out what takes the time when I do a backup of my application data, and found that Firefox, under my 'profile', has a couple of files for the SQLite database it uses - webappsstore.sqlite and places.sqlite. Both were over 50 meg in size.

Looking around the web, people say the 'places' file stores, among other things, bookmarks (I don't have very many) and your browsing history. So I cleared out my browsing history under 'Options' (and, sure enough after that, the Firefox history only shows the last few sites I visited), but 'places' is still as large as ever. I've even tried restarting the computer, in case there was some kind of lock that prevented a clean-up while something was running. I downloaded the 'SQLite Manager' for Firefox, which enables me to examine the contents of these databases, and I find that, despite having apparently cleared my browsing history out, the table 'moz_places' still has over 78,000 entries of what looks like a browsing history - going back possibly years, including websites I can't even remember (that also gave me a 'compact database' option, which has decreased 'places' to about 40M on disk, though still with 78,000 entries; it didn't affect the size of 'webappsstore')

(a) I want to speed up the time for backing up my data, and I don't need to know about 78,000 URLs I've used
(b) there appears to be a privacy problem here. Though I don't share this computer, I would have expected clearing the history to have got rid of this data. But it now seems any software that can read sqlite files can still see my browsing history.

Web pages seem to say 'webappsstore' is for 'DOM storage' - which appears to be a concept like cookies, except that Firefox gives you no way of cleaning it site by site. This is a database table with 8858 entries in, indexed by website. They appear to contain all kinds of things - some are huge chunks of JavaScript, for instance - more than can fit on one screen even in a small font - while others are just numbers or codes with no obvious meaning. A Firefox addon, 'BetterPrivacy', used to have an option of clearing out 'DOM storage', but that has disappeared from more recent versions.

It's possible that it would be cleared out by one of the categories under Firefox's Options->Privacy->Clear Your Recent History, but
(a) I'm concerned about clearing it out for all sites - I don't know what sites that I like and trust (eg Democratic Underground) use it (I don't particularly want to get logged out etc.) - I have cleaned out nearly all cookies, but that hasn't affected this table
(b) it's not clear which of the categories correspond to it
(c) the failure of clearing my browser history to clear up 'moz_places' in places.sqllite makes me think it won't clear the table anyway.

Anyone know anything about these tables and databases? It seems surprising that cookies are well known as objects used by websites that have privacy implications (I get endless "do we have your permission to store cookies?" questions from European websites by law) while this 'DOM storage' seems to fulfil the same function while being far less well known. Ideally, I'd like a way of allowing OK sites (eg DU, places I'm a real customer of) to use 'DOM storage' if they want to, while blocking everywhere else, but I've no idea if that's possible.

[gvstn]

1. I'm not sure I can be of much help.

I read this KB article and it says you can delete that file and a new one will be created: http://kb.mozillazine.org/Places.sqlite

So I closed FF and renamed mine. A new one was created but it starts at 10mb so I am not sure how quickly it grows. FF still remembered my saved passwords, logged in sites and bookmarks. The only thing I saw missing were my favicons which regenerated individually as I visited my bookmarks.

You might want to try the same and run your FF under a new places file for a day. If everything runs fine you can delete your old one and thus your older browsing history.

As far as finding an extension or program that can automatically clear that data on a regular basis, I hope someone might be able to give some suggestions. I, personally, like to keep my History for a very long time as the SuperBar or whatever they call it is useful for bringing up pages I already visited and want to return to, I don't want to do much testing on my installation of FF and accidentally remove my history but I think there is another extension like Better Privacy which I will try to remember the name of.

[muriel_volestrangler]

2. Thanks for the suggestion - my results are just like yours

the 'moz_places' table is now down to 130 entries, which are basically my bookmarks.

I see the equivalent page for webappsstore.sqlite says "Deleting webappsstore.sqlite will delete any data web sites have stored there. A new file will be created when it is needed. ". Maybe if I'm feeling brave (and willing to sign back in again to sites), I'll try renaming that too. What some sites keep in there is ridiculous - I've found entire articles cached in there by qz.com. If I do survive getting rid of it, I hope the Firefox "delete all cookies apart from named sites at close of browser" setting will apply to that too, otherwise I can't see any way of discriminating between sites you're OK with storing some data on your disk, and ones you don't want to.

[gvstn]

3. The good thing about renaming is you can revert.

So if deleting webappstore causes problems then you can close FF and rename the new version to something else and rename the old version back to its original name. FF should make the corrections and run as before.

You might consider using something like CCleaner to delete your cookies. In its Cookie section you can move any cookies you don't want to delete over to the right hand pane. Then when you run the Cleaner it will only remove new unprotected cookies. You just have to get used to using CCleaner to cleanup FF rather than FF's built in erase private data function. CCleaner only marks the cookies as protected from itself not FF so you can't use FF's cleanup if you want to save certain cookies.

If you don't already have CCleaner get the slim version here: http://www.piriform.com/ccleaner/download/slim

[muriel_volestrangler]

4. I've just cut the webappsstore file from 55M to 20M by getting rid of 1 category

(using the SQLite Manager add-on for Firefox) which was entries starting with a Key of "CLOUDFLARE". That was about 1000 web pages, that were cached in the database, from some very boring-looking sites. It would seem that CloudFlare's content delivery strategy is "store it all on the user's computer, so ours don't have to do any work".