(Not sure if this is the place for suggestions, but here's my first impression of this +suggestions)
It looks really clean and nice-looking! I especially like the praise capability.
In order to make the modding site a little less busy at first glance, it might be a good idea to automatically collapse all resolved threads (I know that there's a Pending button, but at first glance it's a lot). If another modder finds something at the same note, then s/he could open up that mod and figure out if the mod was already resolved.
Maybe instead, once the map is updated all of the accepted mods could go away completely as they do not need to be dealt with again (this could also reduce the clutter in the timeline as someone above posted something about).
This is purely aesthetic, but consider on the timeline to put general time frames (0:00, 1 min, 2 min, end time, etc) , because it seems a bit plain with only the lines on it and it would give a sense of where to click to find the place where a mod might be time wise (to check if one suggestion has been discussed or not). I would definitely not put timestamps on all mod lines.
I noticed that when collapsed, there is no way to make there not be shadow on at least one of the boxes, maybe if you click on the same box again it goes back to no shadow.
If something is collapsed and it is selected through the top bar, expand the box. Also, maybe make the sidebar icon also able to do that, but it might take away the functionality of the expand/collapse button... hm