.... so far, I do not recommend it.
"A great introductory language"
There *must* be something I'm missing.
I see her struggling with syntax errors and logical mistakes not picked up in syntax highlighters or bolt-on delinters. The debuggers are a myriad of pages of DOM inspectors, performance tools, js files she's not working with, options for things she doesn't know about and a maze of files, with very little ability to actually step through your running code to see how your "if" statement executes.
The cute little sandbox online simulators take shortcuts.... she spent three hours trying to figure out why she couldn't get a selector hook a click event to a button, running the code in online simulators but not being able to translate it to her code. In the end it was because she forgot to start with a jQuery $(document).ready statement, the simulator couldn't identify that mistake. She couldn't spot it herself because it gave no indication of what might be wrong.
Even turning on strict mode on Firefox doesn't give a single error for a missing $(document).ready, but generates 7 errors for jquery.js.
I used to think Javascript was okay for learning.... but she's programming blind on a lot of stuff. I would love for her to see something like "assigning click event to null object, line 28" or similar, but all I can say is "divide and conquer... test your assumptions at each step, and watch for errors, even if they rarely appear...".. She would have been much better off spending her time working with variables, types and if statements rather than trying to squeeze information out of her programming environment.