How can I put a progress bar for a page that requires an image upload from my customer? I require high-resolution images (around 4 to 8 MB) from a user input and this takes time before the upload is done and user is redirected to my thank you page. This is a very important feature for Wix website premium members like me who have an online store. Can you please add this in a manner of drag-and-drop action only? Thanks in advance.