This article explains important information on how bug fixes, enhancements and browser compatibility are updated and applied in the Progress® Telerik® UI for ASP.NET AJAX control suite:
For best results, we recommend that you use the latest version possible because it will contain the most features and fixes.
Bugs found in UI for ASP.NET AJAX controls are fixed according to priority defined by the product management that takes into account the public Feedback portal, support system, surveys, interviews and other means according to the management discretion.
Bug fixes are introduced in the first official release of the product after the fix is implemented by the development team. Internal (nightly) builds may also contain bug fixes before an official release is available, and you can use them to keep developing your application, but we recommend that you do not promote them to production.
To get a bug fix, you should upgrade your project to a release equal to, or newer, than the first release that contains the fix.
Workarounds for older versions may be provided in the ticketing system if they are technically possible. Progress® Telerik® cannot guarantee that fixes are available for older versions and there is no warranty for any workarounds that are provided.
Feature enhancements and new controls become publicly available in the first major release after their implementation from the development team.
New features and controls are not available for versions older than the first version they are released with.
Versions of the UI for ASP.NET AJAX suite support only the browsers that have been available at the time of their release. For example, a controls version from 2012 does not support IE11, because IE11 was released in 2013.
Suggestions on how to implement a certain scenario or feature in your project together with our tools may be provided in the ticketing system for old versions according to technical feasibility. If such an implementation relies on API, fixes or improvements implemented in later releases, you will need to upgrade to a release containing the necessary feature.