Changing the width of the caption of a figure

[signal mauve]

I'd like to reduce the available width of a figure's caption. I tried using a box, but that produces a linebreak between the caption's content and the 'Figure #:' text. How can I change the width of the caption of a figure?

[magic sand]

If you want to do it for all figures, you can use a show rule. If it should only be applied to a single figure, you will need to scope the figure together with the show rule (or create a custom function for that):

#{
  show figure.caption: block.with(width: 75%)
  figure(image(...), caption: [...])
}