I am trying to clean up broken VTT files, where the lines show: 00:00.000 — constituent 00:06.880 but instead should show 00:00.000 –> 00:06.880 VTT is written so that it’s MM:SS:MSMSMS, and minutes can be any value, so I tried to match that via a regexp using ^d+:d+.d+$, which apparently should work and on some regexp testing places it matches