The notifications i get for Factorio are falsely claiming that literally every new run is a new WR, which is obviously untrue.
For example the top run in the screenshot is not a real WR, see the category: https://www.speedrun.com/factorio?h=Any_MP&x=wkpjq9wk
My suspicion is that it notifies it as a WR if it is the fastest run for that specific combination of run data. That would mean the first/fastest run of any day automatically becomes a WR for notifications since it's the only one with that specific combination of variables + date(+ maybe name?). So far that has been true for every run I've checked.