IE11 hangs when you seek to the end
If you view a video in IE11 and drag the slider to the end of the video, it will often hang IE completely. In some cases, you can't drag the slider back to anywhere else in the video. In almost every case, you can't get the video to resume playing at all, from anywhere. At that point IE becomes unresponsive, refusing even to close. Oddly, if you hit F5, it will finally close the browser.
This happens everywhere, including the demo on the jwplayer.com front page. If it doesn't hang immediately, tinker with it a bit - you shouldn't have much trouble triggering this bad behavior.
So, is this a JW Player bug? No, it's not. I see the same thing in IE11 when viewing a video with a simple <video> tag. So, it's an IE11 bug. I just wonder if JW Player can find a way to avoid it, perhaps by limiting the "seek" so that you can't actually get to very end of the video. On the JW home page, for example, you're safe as long as you never seek past 00:42. But hit 00:43, and you're in no-man's-land.