My name is Alex and I am one of the Support Engineers at JW Player. I will be more than happy to assist you with your questions.
The reason why the tooltips on the first link look different than the second link is that the first link is using JW Player 6. When we came out with JW Player 7, we switched to CSS for the skinning of the entire player. I took a look at exactly what happens when you roll over the chapter marker and the text is provided the tooltip and what happens is nothing, actually. All that happens is that the time, as text, is replaced with the text of the chapter marker. So, as of right now, the only workaround for this would be to adjust the width of that element, but then it would make tooltip look odd when it’s just showing the time.
I’m going to escalate this to our product team to see if there can be something done about this in the future. But, unfortunately, there doesn’t appear to be a workaround right now.
Please let me know if you need any more help or have any other questions.
I'm a bit confused since I downloaded and used version 7, and the problem is still there. Version 7.3.4 to be more precise. But the solution provided by user "a" works fine --->
Yes, all versions of 7 will be affected by the odd sizing of the tooltips for chapter markers. However, I have already heard back from one of our product managers who advised me that they will likely introduce a resolution for this in a future update, but I do not have specifics on a timeframe.
Please let me know if you need any more help or have any other questions.