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revisit of web site auto-fills former own field values, despite cookies deleted

  • I'm used to have cookies deleted upon exit automatically. Just now, I was wondering upon a visit of where a flight inquiry re-appeared that I entered some weeks ago. This happens with Opera 12.16 (Linux). I tried deleting cache and several other things as well, but the behaviour did not change.
    Only by opening a private tab, the entry fields for destination and date are empty. I ask: why? Is any information stored beyond cookies? I'm also sure that the site is not visited while getting in a logged-in state.

    Is anybody able to explain this?

  • Local storage. Go to Preferences > Advanced > Storage and see if they are using any. (It is designed for web apps to store content like documents that might be too large for cookies, but honestly they can use it to store anything.) I believe that Site Preferences should include a setting as to whether to allow a site to use local storage.

  • Old Opera's cookie delete-upon-exit setting applies only to "new" cookies. Have you checked the cookie manager directly to verify that a klm-related cookie might not be present there? Sometimes a cookie is registered without the delete-upon-exit setting having been applied during that session, and when Opera restarts, it defines all cookies still present to be "old" cookies and does not auto-delete them thereafter. This is done to allow a user to intentionally preserve certain cookies for persistent log-in purposes (a feature I found to be quite useful in Old Opera for staying logged in at forums).

  • It was the local storage. Thanks for the hint. I can see that several sites stored information in "local storage". Hm, a sort of cookies that I cannot automatically have deleted upon exit. Such a storage seems not to exist in Firefox, since the "test" yields no issues as complained here.

  • Couldn't you set the "Use application cache" on the storage panel to "ask me" to at least be made aware that this sort of thing might be going on? That's how I have it set, and most of time, when asked, I deny permission with little or no negative impact to page functionality.

  • Sorry for not responding earlier.
    I had set the option "use application cache" to no. But despite that, it is being filled with data. I'll try the "ask me" option. Meanwhile I had the suspicion that other web sites are also using the application cache as alternative cookie storage. When your'e caring about privacy, and you don't realize it, that's quite tricky.

    Question: how can I inspect the contents of such data. Prior to deleting it, I'd like to check whether session data is stored.

  • You can see which sites are storing things using opera:webstorage. You can then browse to the site and use the Storage tab in DragonFly to find out what exactly is going on.

    Access DragonFly by right clicking somewhere and choosing "inspect element" or Page > Developer Tools > Opera DragonFly.

  • The "ask me" option doesn't work either. Local storage is active always.

    Regarding Dragonfly: Marvellous feature!
    I'm able to check what's going on in local storage, e.g. googleads.g.doubleclick.
    Now I'd want to autoclear the local storage upon closing of opera...