modalCloseContent option doesn't appear to be working

[kaydanzie]

JSFiddle replicating issue: https://jsfiddle.net/zhuxdyfb/

In the fiddle, no matter what you put in data-modal-close-content, it doesn't change the default × content. Am I using it wrong?

Implementation is based on this config option, and this line should be replacing the default value with what I put in data-modal-close-content so I'm not sure what's happening.