While I certainly agree that the reverse box model makes some aspects of front-end development easier, let us not forget several things:
+ Kendo UI and Bootstrap were introduced at the same time (August 2011). Back then, Bootstrap was not popular, while Kendo UI was a successor of a product that existed since 2009 and it used the default box model
+ not everyone is using Bootstrap or the reverse box model
+ switching from one box model to the other now or at any moment would be the biggest front-end related breaking change that we could possibly inflict
+ while Bootstrap may need reverse box sizing for its own DOM elements (i.e. CSS classes), it is unclear why would they need to enforce such a sizing unconditionally to all elements on the page via the universal selector (*), thus breaking all other third-party libraries, which do not rely on border box sizing
Nevertheless, it may be possible to achieve seamless integration between the two products if we introduce some non-breaking changes to our CSS code. We are currently investigating this opportunity.
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