ScreenFlow User Guide
Text Capabilities — Changes over Time

Video Properties

All of the Video Properties applied to Text Box clips will be respected as part of a Video Action.

This allows Text Boxes to move around the canvas in 3D as with any other Media in the Timeline.

Since they also respect Opacity, it's a snap to build simple Fade-In Transitions using Text Boxes.

Text Properties

None of the Text Properties are currently changeable over time for a Text Box clip.

This means that when you change properties of a piece of text, those properties are changed for that Text Box clip for the whole length of the Timeline.