Calling openDzi() more than once causes timer leak


The _updateMulti timer continues to reschedule itself until it notices that the image has been closed. Each call to openDzi() (i.e., when switching DZIs) starts a new _updateMulti timer, but because other instances of the timer never see a closed image, they also continue to schedule themselves. Calling close() before openDzi() doesn't avoid the problem.

Workaround: Switch DZIs by closing the existing viewer, emptying its div, and creating a new viewer.