The scroll property of the VTTRegion interface is an enumerated value indicating how existing cues in the region move when a new cue is added.
A string. Possible values are:
"" (the empty string)Existing cues in the region don't scroll; instead, they are displayed at the same time as new cues. This is the default.
"up"New cues are added at the bottom of the region, and existing cues scroll upwards to make space for them.
In the following example, a new VTTRegion is created, then the value of scroll is set to "up". The value is then printed to the console.
const region = new VTTRegion();
region.scroll = "up";
console.log(region.scroll);