Question

How I can save() all CodeMirror textareas on one page?

Answer 1

You’d have to cache all CodeMirror instances in to an array, and then loop through that array save()‘ing each instance.

var CMInstances = [instance1, instance2, ..., instanceN];
for (instance in CMInstances) {
  instance.save();
}

I’d assume at some point in your script you’re setting up your CodeMirror instances, so that point would be ideal to cache them.