In an open modal window, if you want to use the modal window to accept the server's stream, you usually need to hide an iframe; sometimes, you then use the form of iframe.src to make the request; sometimes, you find that the server cannot receive the iframe's stream during downloading. , because the src redirection event of the iframe is not triggered in the modal window, and ordinary windows do not have this problem.
Specific solution:
Hide an iframe in the parent window of the modal window, and the download address points to this iframe.