I'm writing a new web application that needs to support drag and drop operations for elements on the page (not file drag and drop).
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recommends using Modernizr to check whether the browser supports HTML5 drag and drop and either use that support or fall back to an alternative like jQuery UI.
Since they have quite different models, that means that all drag and drop code would have to be implemented and tested separately (very little shared implementation). It only seems logical to do that if there are significant, user-impacting benefits to HTML5 drag and drop and if the fallback to jQuery UI would provide a degraded experience.
Are there significant benefits to implementing both variants?
I would guess that eventually jQuery will take advantage of built-in browser capabilities like html 5 drag and drop.
And if different browsers implement it differently...jQuery will deal with it.