GWT setCapture works in Firefox too, how?

I have a draggable element in my page. When user starts dragging and then releases mouse button outside of Firefox I need to receive mouseup so that I can sto开发者_运维百科p dragging.

IE has setCapture for this but FF doesn't have. GWT has it too which works in FF too.

How does it works in FF? How can I do that in my JS code for FF?

(I like to know how it works, not just using xyz JS framework).

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Well the answer is to add mousemove and mouseup event listener to document.

Thanks @Jeremy!