To my surprise that appears to work (I’d never tried it and had to make a test sketch to see if it would work). I dragged in three 2 pin headers in to breadboard and connected one pin from the first two to a single pin on the third in breadboard, then switched to schematic. In schematic the connections are correct. It is however probably a bad practice because on a real Arduino you can only get a single wire in to the header and the idea in breadboard is to have something you (and someone else using your sketch) can physically wire up, so you should use a breadboard strip so each wire has its own hole. It is also likely to make verifying the connections are really connected more difficult as sometimes a connection can look like it is connecting on the screen but it a bit off and there is really no connection in the other views. A good connection should go green (rather than red) and when clicked on everything connected should go yellow but with two wires on a single pin I’m not sure what will happen if one wire is connected and the other isn’t (I suspect the other end of the non connected wire won’t light up yellow, but that may not get noticed).
Peter