another Polymer 2 problem

[davidmaxwaterman]

I have found that there is an issue when using a dom-repeat's index in a drop-item - while before, in Polymer 1, the dom-repeat would do whatever is necessary to make the index value correct, with Polymer 2 it doesn't, so the index follows the item that was dragged. I guess this is trivial to show in the demo just be adding a binding to index.

TBH, Sortable actually moving the dom elements around inside the dom-repeat to be quite suspect, and has lead to all sorts of issues with dom-repeat....my solution is to abandone dom-repeat and do my own manual implementation.