I am having the same issue. I have TT Desktop Deluxe (PC version). When I try to import Fidelity transactions, I get presented with the Turbotax login screen but it isn't usable. I have tried it with Edge and Chrome as my browsers (although I am not sure the desktop version requires browser access). I have the 2/23 update. I have rebooted my PC with no luck.
Why am I required to login to Turbotax anyway when I am importing transactions just from Fidelity? When I downloaded from Vanguard I didn't have to do this. It is extremely frustrating!
