I think there is some kind of bug with the duration display, because on my screenshot it shows 0:52, even though I was actually at around 0:28. I encourage you to submit another Show HN in half a year though. I've been on a lookout for a free web-based video editor recently, and haven't really found anything to my liking. I even had thoughts of making my own but never actually got to it.

Its position in the timeline is shifted 23 sec as i see so the duration is fine. but If u mean the source end time yes, its not causing any trouble for now, but I will work on making it accurate.