For anyone else who don't/can't/won't run LiveSplit, the relevant registry path is HKEY_CURRENT_USER\Software\will herring\Pet The Pup at the Party
I agree that it isn't ideal, and I'm pretty sure I've brought this up with other runners before, but the issue is actually timing this correctly and fairly - and it will definitely conflict with current leaderboards.
Ideally it'd need to be implemented in the autosplitter, but its already janky as-is (the autosplitter mostly relies on registry reads IIRC) and there has been very little interest from anyone to maintain or improve the autosplitter.
Another issue is that the community is mostly dead (almost no speedrunning talk on the Discord for the last 2 years) so I doubt any current runner is effectively willing to take charge.
Should interest get revived (basically just be vocal on the Discord server I guess) I'm sure we can work something out.