[browser] favicons are not persistently cached on disk

[Olivier Tilloy]

Since version 0.23+14.10.20140709-0ubuntu1 of webbrowser-app, favicon support was re-introduced (it had been initially removed when switching to oxide). As of that version, the bookmarks list on the new tab page displays favicons. However the favicons are not cached on disk, all we store is a reference to their URL (e.g. http://assets.ubuntu.com/sites/ubuntu/latest/u/img/favicon.ico). Once the icons have been fetched by the QML engine, they will be cached in memory during the lifetime of the application, but if the application is killed and restarted, the icons will be fetched from the network again, potentially incurring a cost on the data connection.

Favicons should be cached on disk to avoid re-downloading them every time the app is launched.

[Olivier Tilloy (osomon)]

I added an ubuntu-ui-toolkit task to this bug as there was a mention a few weeks back of a generic and transparent mechanism in the UITK to implement a persistent image cache.

As far as I know, the feature was first implemented in unity8 (to persistently cache icons in the apps scope), with a plan to make it more generic and move it to the UITK in the future (see this thread for reference: https://lists.launchpad.net/ubuntu-phone/msg08632.html).

[Zsombor Egri (zsombi)]

As far as I know there were no plans to have such a cache in toolkit. However we would be glad if someone would contribute that to the toolkit.

[Launchpad Janitor (janitor)]

This bug was fixed in the package webbrowser-app - 0.23+14.10.20141003-0ubuntu1

---------------
webbrowser-app (0.23+14.10.20141003-0ubuntu1) utopic; urgency=low

  [ CI bot ]
  * Resync trunk

  [ Alexandre Abreu ]
  * Add a simple mechanism (simpler than the one already in place) to
    override user agents for a given webapp. (LP: #1370975)

  [ Alberto Mardegan ]
  * Fix handling of host cookies

  [ Olivier Tilloy ]
  * Ship a PNG icon instead of an SVG, and install it under the app’s
    own data dir. (LP: #1365408)
  * Make an autopilot test more robust by ensuring that the drawer menu
    is dismissed but not clicked. (LP: #1365304)
  * Persistently cache favicons on disk to avoid re-downloading them
    across application runs. (LP: #1340585)
  * Ensure that at most 2 webviews are instantiated at all times, to
    reduce memory consumption. (LP: #1376418)
 -- Ubuntu daily release <email address hidden> Fri, 03 Oct 2014 14:42:27 +0000