Details:
- The squares are svg:use elements, pointing to an svg:rect, defined inside a svg:defs.
- On mouseOver, the svg:use will have its xlink:href pointed to the red defined svg:rect.
- On mouseOut, the svg:use will have its xlink:href pointed back to the blue defined svg:rect.
- On both mouseOver and MouseOut events, the event type and the rectangle (svg:use) ID will be written in the log on the right hand side (inserting at the top).
- This redefining of the element causes a second mouseOver event to be triggered, which is understandable and can be filtered out based on currentTarget and relatedTarget event properties.
- Now, when you move around your mouse quickly over these squares, sometimes no mouseOut event will be triggered for some element. Actually, this element will only have had one mouseOver event triggered. I guess before the element is changed (causing the second event), the mouse pointer has already left the element. Shouldn't then at least the mouseOut still be triggered? In some cases an element only shows one mouseOver and one mouseOut event though, which would match a too quick movement like before. That would then mean that the previous issue is an actual bug?