Last modified: 2011-09-07 23:28:04 UTC
When someone clicks Donate via PayPal, the extra data should be added by an AJAX API call rather than sending them to a redirect page. A spinner should be activated on the page in case the API call takes a long time.
This is actually related to ContributionTracking rather than DonationInterface.
Assigning to Katie as she's currently working on this.
This can now be accomplished through the new ContributionTracking API. The extension also comes with a working example, accessible through the new ContributionTrackingTester special page (sysop only). However: There is, as yet, no spinner.