The Wayback Machine - https://web.archive.org/web/20130910203451/https://dev.twitter.com/issues/progress

In progress API Issues

The Twitter API issue tracking system is used to report and give you update on bugs found in our APIs and widgets. Before reporting any new issue, be sure to check developers discussions and the issues list. Also note that existing issues are automatically linked to the documentation pages and discussion threads they're related to.