This sort of builds up on this and this previous question. Both of them ask about if the President can block the transfer of their office to a successor.
In response to the current Coronavirus pandemic, many states are encouraging people to use “social distancing” methods and canceling large public events to prevent the spread of the disease. With large numbers of people using the same voting booths and voting machines, in-person voting seems like it could provide an effective vector for the spread of the disease, and if the pandemic continues to get worse it’s possible to imagine in-person voting being significantly disrupted.
In this situation, what would happen if the coronavirus (or another pandemic) significantly disrupted in-person voting for the Presidential election? Would the election be delayed, or are there mechanisms to enforce a change in voting methods? In this kind of hypothetical situation, how would the successor of the U.S. President be (s)elected?