Subtitles
noun
A curtain of letters that goes on your screen are subtitles. Sometimes they have black bar backgrounds too, which are like curtains!
じまく
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
字幕のせいで気が散ることもあります。
Subtitles can be a distraction.