I’m having issues adding text labels into the graph. Trimming the code down, this is what I’m trying to do:

var element = document.createElement('canvas');            
var context = element.getContext('2d');
context.font = "10px Arial";
context.fillText("X", 10, 10 );   // problem here

If I include that last line, the module breaks. What’s the right way to put text in a a Canvas box?

Also, when I break modules doing stuff like this, how do you see an error message to get an idea of what went wrong?