P: Splitting a caption causes a third, tiny copy to get added to the end

Selecting a caption and clicking the Split Caption button in the Text > Captions pane is often causing me to get a third copy of the caption get added at the end of split one (now two). It's often very small in the track and only found by seeing it in the Text > Captions list. I'm not sure of any other correlates to this weird behaviour.

Version 24.5.0 for Win 11.