UART DTE with multiple stop bits
Stop bits are effectively an idle signal - sending 2 stop bits just means that the receiver will sees an extra 1 bit gap between the characters. 

Serial asynchronous data format is: idle (high) start bit (low) data bits (anything) optional parity (anything) stop bit (high) idle(high) 

The receiver recognises the start of a character being sent as the first low transition on an idle line (start bit).  No of stop bits is irrelevant.

RTS / CTS control signals are control signals they do not have any stop bits.