With the release of Q3.2008 we made certain changes in the rendering and respectively with the styles of RadFormDecorator's skinned buttons, and we decided to drop the support for ForeFox 2 for the sake of improving the performance with Chrome and Safari. In the previous versions of RadFormDecorator the skinned buttons were actually block elements, which were floated to the left, which had nothing in common with the real buttons, which are inline elements and this caused many problems. Later on, we used the inline-block property for Internet Explorer and Opera, and a combination of several -moz properties to achieve inline behavior for FF. In version 3.0, FireFox finally implemented inline-block, and we decided to stick to it rather than to use the -moz properties, because they caused a couple of other issues that were very hard to handle.
As FireFox is a standards compliant browser (well, mostly) it is not possible to query separately 2x and 3x versions, simply because FF hacks do not exist. This is why we cannot offer you a 2x-specific solution, and on the other hand FF versions are being released every 3-4 weeks, and these minor versions ofter offer different support for similar properties, especially the -moz- prefixed ones.
All the best,
the Telerik team
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