But my KM action (to save the value in a variable) returns nothing. I've tried varying numbers of backslashes to see if I needed to "escape the escape", so to speak, but no luck with any of it.
Well, bugger me, it's working now. I swear I tried this already but anyway, I created a new action:
Execute JavaScript in Safari
document.querySelector("#N10\\:PayElementRunAmount\\:0").innerText
Save trimmed results without errors to variable “RunAmount”.
Stop macro and notify on failure.
Now my variable has a value.
I can't share the URL since it's private but here's a snippet of the page: