As Boyan has noted, the change is not a bug or an issue, instead it's an improvement in terms of usability, as outline in the forum thread he referenced -- http://www.telerik.com/community/forums/aspnet-ajax/combobox/possible-breaking-changes-2012-q3.aspx
The main point of this improvement is:
-- if it looks like a textbox, then you can write in it (ComboBox with custom text, RadInput)
-- If it looks like a button, then you can select a value from a list (Combo w/o custom text, DropDownList etc)
There were, as pointed out in this thread some visual discrepancies and we are targeting them.
That said, there are customers like you, who are not pleased with the way the control looks. In such cases we prepare a modified version of the sprite image. To do so we need to know the skin you are using.
Note:The above modifications do not apply for any skin newer than 2012 Q3 (currently BlackMetroTouch, Silk and Glow), as well as for ComboBox light-weight rendering skins.
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