Ah, sorry, the whole button CSS for the API button that I was generating (no idea if it's even remotely similar for character sheet buttons) would be: '<a style="background-color: '+backColor+'; padding: 0;" href="[Whatever your Command is]">'
+'<div style="width: 24px; height: 24px; '
+'display:inline-block; margin: 0; border:0; cursor: pointer;padding:0;background-image: url(\'<a href="https://app.roll20.net/images/statussheet.png\" rel="nofollow">https://app.roll20.net/images/statussheet.png\</a>');'
+'background-repeat:no-repeat;background-position: '+((-34)*(i-9))+'px 0px;"></div></a>' The code that this is from has a few different versions of this and generates this as the output in chat based on a few parameters that it is passed: Each one of those statusmarkers is a clickable button.