title: setting cross origin variable in iframe
body: <p>i am embedding a form on a checkout page with an iframe and i am trying to take the price of the cart and have it automatically inputted into the amount field. the value of the cart variable seems to be <code>$("span[data-test='cart-price-value']").innerText;</code>
  when i check it in the console, but i am confused on whether i should set the variable in the script that embeds the iframe or in my iframe html itself or whether or not i have to do both and add a jquery listener to the iframe html </p>
  
  <p>and also i need to trim off the '$' from the variable, cause 
  <code>$("span[data-test='cart-price-value']").innerText;</code> returns a value with a dollar sign in front of it for example "$435.66" and i need it to be just "435.66" any help would be appreciated </p>