Today, we are pleased to release XenForo 1.5.12. This release fixes a number of bugs and issues that were found since the previous release. As this is a maintenance release, the vast majority of the focus was an increase in stability.
However, by default, we have replaced the Flash-based attachment uploader with an HTML5-based approach. This has increased compatibility with mobile devices and removes Flash as a dependency for multiple file uploads. The Flash-based uploader is now deprecated. While the HTML5 uploader is enabled by default, you can change back to the previous uploader code by disabling the "Use new HTML5 uploader" option. Generally this should not be necessary; however it's possible the new uploader may not be...