Hi!
I think you have stubmled upon a bug, that had not been discovered yet. I was able to replicate the issue, the slider is not triggering always, as it should. Interestingly, when ‘tapping’ on the slider, it does work, but dragging does not. I suspect something might have changed with how the browsers handle the drag events – or I have made a mistake somewhere in combination with the new features.
I will have to debug this in-depth, I don’t think it is possible to quick-patch with a custom code. I have made this a top priority issue regarding the upcoming release, it should be fixed within the next patch. Sorry about the inconvenience.