The customization options for Closed Captioning have borders are too thin to be usable without a background unless the text is made unreasonably large.
Anime subtitles (English Sub) use a format of white text with black outlines and often some dropshadow and no background (the hideously black bar). It limit obscuring the image. I tried to replicate this standard but those other streaming services (or bootlegs) have a notably more readable contrast than what the Roku system CC is showing.
It is almost usable though which is odd. Only some backgrounds, colors or images make the text difficult to discern which makes me think it's only short by a pixel or so.
Maybe add a new way to adjust dropshadow thickness or dither.
