This issue was resolved for the RadGrid "Filter menu" but the problem still exists for the "Column Header" menu. The pop-up menu that you get when a user right clicks the column header (for sorting, grouping commands, etc) is still not positioned correctly in IE11 when horizontal scroll is enabled. Please fix ASAP.
This problem was reported and acknowledged April 2014 and it is still not fixed. We have to use a 1 year old version of Telerik libraries to avoid this problem in our applications. There is no point renewing our licence if we can not use the new quarterly revisions.
When will this issue be resolved?