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Type: boolean
Set this attribute to true to have the cursor switch to a waiting cursor while the mouse is hovering over the element. Usually, you would only use this on the window element or other top-level elements. In order to revert to the normal cursor state call the method removeAttribute("wait-cursor") when the process effectively has ended otherwise the wait cursor might never disappear.

See also

This seems to work instead of trying to set a wait-cursor attribute:

window.setCursor('wait') and window.setCursor('auto')