Without going too much into detail, I noticed that all of the browsers (Safari, Chrome, Firefox) stopped supporting timeline features such as "mouse over" action to continue timeline a new timeline (essentially on hover) when previewing Hype project. I couldn't understand why it was happening so I restarted/quit all browsers and hype which didn't help and btw, it also effected projects html files that were hosted.
Finally, I restarted my Mac and everything started working accordingly. Has anyone experienced this?
I should say this is just a guess, since it seemed that disparate apps were behaving in the same way, indicating an error in a system common to all. It is impossible to say what the actual problem was, especially now that it has gone away!