The expensive part of a bug is rarely the fix. It is getting it to happen again. A ball goes through the floor once in twenty tries, an enemy turns around for no reason, a jump fails on one frame, and by the time you notice, it is gone. So you add Debug.Log everywhere and press Play again.
Hindsight keeps the last seconds of your game in memory while you play. When something looks wrong, you pause and drag the timeline back. The real objects move back to where they were, so the Scene view and the Game view both show the past, with your materials and lights. Errors and bookmarks sit on the timeline: click one and the scene jumps to that frame. Select an object to read its position, its velocity and your own [HindsightTrack] fields at that frame, with a graph over the whole recording.
It costs a few hundredths of a millisecond per frame in the editor, allocates nothing while recording, and none of its code runs in your builds. I tested it in my own HDRP game on Unity 6.5, and that test found two bugs the demo never showed. Both are fixed in 1.0.2.
It is free and MIT licensed. Install it from the git URL in the README: https://github.com/Nekuzaky/Hindsight
If it saves you an evening of Debug.Log, a coffee is always appreciated.