Google Chrome: Add option to purge Content Data

[VanguardLH]

(Originally I noticed the zoom history was storing a list of sites I visited where the zoom level was changed and that's what I started noting in my report here; however, then I noticed per a bug ticket that the zoom history would get purged by using Chrome's "Clear browsing history" function and electing to include "Content settings".  Yet CCleaner has no option to include purging of Chrome's content settings - so users are stuck having to use both Chrome's "Clear browsing history" with content data selected and then using CCleaner.  A cleaner CCleaner usage would be to have CCleaner do the Content Data purge.)

CCleaner does not erase the zoom level history in Google Chrome.  While the stored zoom level is not a privacy issue, having a list of sites that you have visited (where you happened to change away from the default zoom level) is a privacy issue.  CCleaner will erase other privacy data, so why doesn't it have an option to also erase the zoom level history?

In Google Chrome, go to Settings -> Advanced -> Content settings, scroll down to Zoom level (or go to chrome://settings/content/zoomLevels), and there you will see a history stored of the sites where you changed away from the default zoom level.  Besides a privacy issue, Chrome only lets you delete one site at a time to remove it from this zoom history.  That can take a long time if the user has change the zoom levels on lots of web sites.

See http://www.rawinfopages.com/tips/2014/11/reset-chrome-zoom-levels-for-websites/ on how the user must currently and manually delete the zoom history one site at a time.

Firefox cleanup can include the Preferences it stores per site.  I remember it is an on-exit cleanup option in Firefox.  I don't have Firefox currently installed to see if CCleaner also has an option to purge Firefox's [per-site] preferences settings.  It should.  If it does, it should have similar options to purge preferences settings in Chrome, like the zoom history.

According to comment 38 in the https://bugs.chromium.org/p/chromium/issues/detail?id=137412#c29 bug ticket where users have been asking for a zoom history cleanup option since 2010, dullweber claims there is now an option to purge Site Settings when purging browsing data from Chrome.  That comment was back on Oct 5, 2017 yet there is still no such setting but there is the Content Settings included for purging that data from Chrome; however, that requires that I manually run the browser cleanup from within Chrome.  There is no purge-on-exit function in Chrome, and why users have turned to extensions, like Click&Clean (but that is nagware is interferring with presenting a spam page about changes in a new version of the extension instead of going directly to the URL, and bitches Chrome isn't at the latest version).

In CCleaner, why is there no setting for Content Settings to let the user elect to include those settings and histories from Chrome when running CCleaner?  Why do users have to resort to navigating through Chrome's menus to purge browsing history instead of using CCleaner?

There is a "Keep local data only until you quit your browser" option under chrome://settings/content/cookies.  While it includes cookies and perhaps site data, the zoom history is unaffected by that setting.  Plus, if enabled, Chrome will cease to automatically log into the user's Google account when loaded (you will see "Paused" at the top right of the toolbar in Chrome which requires you reenter your password to unpause the sync in Chrome).  CCleaner has an option to delete Chrome's cookies and another option to delete Chrome's session data, so why not an option to also delete the content data as well (which will include the zoom history)?

CCleaner is a privacy and cleanup tool.  Not including Content Data in cleaning up Google Chrome is a big miss by CCleaner.

[nukecad]

I believe that you may have touched on your problem yourself; the sync setting.

CCleaner can only clear what is on your machine.
CCleaner does clean Chrome history, see the screenshot in this post:

However:

When you have syncing enabled your settings, history, etc. will also get saved on Google's servers so that it can be synced.
That's why 'Keep local data only...' pauses the syncing (ie. stops saving it on the Google server)..

If you use syncing then when CCleaner, (or anything else including yourself), removes this synced data from your computer the syncing just puts it straight back again.

You can delete it as many times as you like locally but the sync will keep putting it back until it is removed from the sync server.
Obviously CCleaner does not have access to Google's sync servers to remove it, so that has to be done within Chrome if you are syncing.

[VanguardLH]

nukecad, nice stab at trying to determine the source of the problem but it assumes that CCleaner is purging the zoom history (part of Content Data) and that Chrome's sync is putting it back.  Nope, not true.

Disable Chrome's sync.  Visit a number of sites where you change the zoom away from the default, like using Ctrl+mousewheel to zoom in or out.  Exit Chrome.  Reload Chrome and visit chrome://settings/content/zoomLevels.  Yep, those sites where you changed the zoom level are STILL listed in Chrome's zoom history.  And that was with Chrome's sync disabled!  CCleaner is not deleting the zoom history which is part of "Content settings", so it is suspect that CCleaner is touching any of the content data in Chrome.

Chrome's sync is not getting in the way of CCleaner purging the zoom history because sync was disabled and yet CCleaner isn't purging Chrome's zoom history.  CCleaner missed on purging the zoom history - and that's a list of sites you visited (and changed the zoom level) which means the web browser is retaining a history of your web visits - and that's whether Chrome's sync is enabled or not.

Just what of Chrome's Content Data is CCleaner coded to purge?  If zoom history is getting missed, what else is CCleaner missing of "content settings"?  I have Chrome configured to included "Content settings" when I use its "Clear browsing data ..." (Ctrl+Shift+Del) and that works to flush out the zoom history.  When there is some zoom history (the list is non-empty), I exit Chrome, and run CCleaner, but the zoom history is still there when I next load Chrome.  And, no, sync wasn't restoring zoom history because sync was disabled during the test.

Per your argument about Chrome's sync, even Chrome's own "Clear browsing data ..." function would fail since everything cleared by the local client would simply reappear after the next sync.  You would never be able to clear anything using Chrome's own cleanup function.  With Chrome's sync disabled, your hypothesis failed because the zoom history was still there after exiting Chrome, using CCleaner, and reloading Chrome.

Since zoom history is not cleared by CCleaner, and especially since there is no "Content settings" or "Content data" or "Site preferences" option for Google Chrome under CCleaner's Application tab, doesn't look like CCleaner wipes any of the content data.  Trying to figure out just what is included with each option listed in CCleaner as to what it will clear has always been vague.  Through testing, clearing history and clearing session data do NOT include clearing of content data (aka site preferences).

Perhaps, like Firefox, Google's Chrome is saving its settings inside an SQLite database file.  Purging "content settings" might be only some of the settings stored in the SQLite file, so simply deleting that .sqlite file would delete more than just the content data.  SQL commands could be used to delete records in an SQLite database provided the logical data structure, like record names and fields within each record type, were known.  Either someone at Pirifom missed the clearing of content data (aka site preferences), which includes zoom history or they haven't figured out how to dig into Chrome's database files to target just the content data without touching other records that are not part of content data.  I'm hoping it wasn't a miss by Piriform to include an option under the Google Chrome app in CCleaner that would target content data and instead one of those "Can't do it because the database has mixed data types, so cannot target just content data".

 

[hazelnut]

Not an answer as such but more info perhaps.  

http://www.rawinfopages.com/tips/2014/11/reset-chrome-zoom-levels-for-websites/

Been asked about for a long time.

https://superuser.com/questions/203669/make-google-chrome-forget-zoom-level-once-a-tab-is-closed

[VanguardLH]

hazelnut, the rawinfopages article was already mentioned in my opening post.

As for an option within Chrome to purge the zoom history, I also included a link to a bug ticket asking for that feature to Chrome (which also linked to even older threads asking for the feature).  The feature was added; however, the bug ticket says to add "Site settings" to the items included under "Clear browsing data" but, in fact, it was the "Content settings" item that got added (or Site Settings was included under Content Settings) and under which zoom history got included.  Using Chrome's own "Clear browsing data" and including "Content settings" will include the erasing of zoom history.  So, I can do it using "Clear browsing data" (by adding "Content settings") within Chrome but not by using CCleaner which has no "Content settings", "Content data", or "Site preferences" item under Google Chrome in the Applications tab for CCleaner to purge that data from Chrome.

Extensions can purge Chrome's browsing data by using an API.  See:

https://developer.chrome.com/extensions/browsingData
However, none of the data types is clearly content data aka content settings aka site settings/preferences.

CCleaner is not a Chrome extension, so it has no access to this API within Chrome.  I remember trialing the Click&Clean extension a couple times but gave up both times due to it being nagware: when I specify a URL to visit in the command-line to Chrome, this extension interfered with my use of the web browser by instead showing a "What's New" page that I'd have to close, and later they added another nag when my instanced of Chrome is not at the latest version.  Too many nags to keep using this extension, but it did have a handy option to purge on Chrome's exit.  Actually, Google screwed that up so extensions could no clean on exit and instead they have to perform the cleanup when they load (and that's when you start Chrome).  If that extension were still installed, I could test if it included the site settings that CCleaner misses nor even has an option to include.

 

[hazelnut]

Apologies for repeating the link you already posted (it obviously must be a good link!)

I don't use Chrome which means I cannot use my own machine for clues so forgive any obvious questions I ask.

Do you have a Preferences file in your user directory for Chrome. If yes does it have the zoom info there which you could copy the path from to add as a CCleaner 'include'?

[VanguardLH]

My guess is the zoom history (or per-site preference) is stored in:

C:\Users\<myAccount>\AppData\Local\Google\Chrome\User Data\Default\Preferences

Within that file, I found the following string (newlines added for clarity):

{"default_zoom_level":{"x":0},
  "per_host_zoom_levels":{"x":
    {"<siteURL>":{"last_modified":"13193563712019947","zoom_level":2.223901085741545}},...
    ...
}

which looks something like XML where the default zoom level (as an offset) is specified followed by records within that record for specific sites and their zoom levels.

That is a text file with no extension.  However, more than per-site settings, like zoom, are stored in that file.  It looks like a lot of other settings are stored in that file.  This file stores my preferences - all my preferences (aka settings) - not just the default and per-site zoom levels.  Deleting the file would result in effecting a reset of my Chrome profile, so I'd be starting from scratch again.

Yeah, I could have CCleaner delete the Preferences file but then I'd be back to the initial start of Chrome.  Since you are familiar with Firefox, that is the equivalent of using its Refresh button that gives you a new profile to let you start again from scratch.

While I was guessing the Preferences file stored a lot more than just the zoom history, I found a forensics article that mentions Chrome's configuration (not just zoom history and not content data) was stored in the Preferences file.  See:

http://www.forensicswiki.org/wiki/Google_Chrome

Also, apparently CCleaner has been the cause of corrupting that file.  Perhaps Piriform doesn't know the correct syntax of the XML-like records in that file or the definition of some of its records.  See:

https://techdows.com/2013/11/fix-chrome-your-preferences-file-is-corrupt-or-invalid.html
See the "Check if CCleaner is corrupting Chrome preferences file"

That's an old article but apparently users were encountering problems in the past when using CCleaner to clear Google Chrome.  That CCleaner is or used to corrupt the preferences file hints that Piriform is parsing the contents of that file to determine what to null out.  Well, if true, why aren't they also parsing out the zoom histories for per-site settings stored in the Preferences file?

Deleting the Preferences file is not an option to merely eliminate the per-site zoom history that in itself is tracking data (and why I was hoping CCleaner would clear it).  The effect would be to slam Chrome back to all its defaults for ALL settings, not just eradicate the history entries therein.
 

[Andavari]

Looks like one of those things that would have to be "surgically removed" by cleaning tools then. Too bad they Chrome/Chromium doesn't just have it as a single file that could be deleted without repercussions.

[nukecad]

Fine that woud seem to rule out the syncing being your problem here.
(But it's always something to bear in mind. When you put something in 'the cloud', on someone elses servers, you don't always have full control of it).

Quote

Just what of Chrome's Content Data is CCleaner coded to purge?

That's the question, and it could only be answered by the developers.
Obviously they may not want to give away just what it is set to find and clean or how it finds it, businesses don't tell their rival what they are doing.

You could do an analyse with CC and look at the filelist of what it finds for Chrome to get a clue.
But of course that would not tell you what it is not finding/cleaning.

It looks like you have already dug deeper and done your own investigation of where this data is being saved, and found it.
But it's not going to be easy to strip out unwanted data from that file and leave the rest.
And if you did write a routine to do that then who's to say that Chrome won't change things again next month?

It's one of the problems for third party apps that work with browser (or system) data.
The current browsers (and even Windows itself) frequently (monthly updates) change how they work and what they store and where, the third party app developers then have to find out just what they have changed and react to it - if they even can. (By which time it may have changed again).

It's one of the reasons that CC has simply dropped cleaning of certain things in the last year, eg. CC no longer cleans Windows Update Files.

With the likes of Google and Microsoft  it may be a deliberate attempt to make third party apps unusable, Google have well reported plans to cripple adblockers soon. (And Firefox are set to follow).
https://www.ghacks.net/2019/01/22/chrome-extension-manifest-v3-could-end-ublock-origin-for-chrome/

PS. If sync is on and you clear browsing data from within the browser then it will be cleared from the sync server as well.
But a 3rd part cleaner can never touch the server, only the browser.