Web sites typically incorporate a small graphic -- called a "favicon" -- that the user's browser can display on a tab, like so:
Most Drupal themes, including ours, allow the administrator to configure the favicon as part of the theme settings.
Apple browsers have their own expectations for these, called Apple Touch Icons that come in a variety of sizes. Unlike favicons, most Drupal themes do not directly support them. As a result the Drupal log often has many "page not found" error messages. This is an annoyance for the site administrator and a slight inconvenience for Apple users.
In order to provide Apple Touch Icons, I first took the main IAC logo file, reduced it to the various sizes Apple expects to have available, and uploaded them to the files/AppleTouchIcons directory. I then added and enabled the Metatag module and its favicons sub-module. Then I navigated to the Metatag configuration page, and in the Global section added the paths to the various icons. Now each page contains links to the icons, thereby satisfying the expectations of the Apple browsers and eliminating the error messages.
