The base font size expressed as a percentage of the video height.
Mac Catalyst 13.0+Beta
Value must be a non-negative CFNumber. This is a number holding a percentage of the height of the video frame. For example, a value of 5 indicates that the base font size should be 5% of the height of the video.
This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.