1WEBVTT 2 3spaces 4 00:00:00.000 --> 00:00:01.000 5 text0 6 7tabs 8 00:00:00.000 --> 00:00:01.000 9text1 10 11form feed 1200:00:00.000-->00:00:01.000 13text2 14 15vertical tab 1600:00:00.000-->00:00:01.000 17invalid 18