Currently only used for write_svg()
Examples
cast <- read_cast(system.file("examples", "hello.cast", package = "asciicast"))
svg_file <- tempfile(fileext = ".svg")
mytheme <- modifyList(default_theme(), list(cursor = c(255, 0, 0)))
write_svg(cast, svg_file, theme = mytheme)
# \dontshow{
unlink(svg_file, recursive = TRUE)
# }