How To Insert Variable Into JavaScript Action

[JMichaelTX]

@CJK

I've highlighted a portion of text in that image; the value 650 . I'd like to subtitute that value with a KM variable that one can set beforehand, but can't see a way to do this given that the text script editing field is one of the few types of input fields in KM that doesn't process text tokens.

See Execute a JavaScript in Browser actions

Is there some reason this would not work:

var imageSizeStr = 'l' + document.kmvar.ImageSizeStr + 'x';
return "!["  + p1 + imageSizeStr // + the rest of this line