1 normal mode (not logged in), log in to page B in page An and enter the account password. After success, return to page A (the entire parent window is page A)
2 problem mode (page B is already logged in), open page A, and the embedded page B determines that you have already logged in, so jump back to page A directly, but then page A will appear in the location of page B embedded in iframe on page An and page A will be opened. ( that is, it jumps to page A directly in iframe, but does not open page An in the parent window )
so please ask how to solve this problem?