I’ve been experiencing the same problem as @Doohie and @megawattz . Only reason I was able to log into Bitwarden this morning is because I’d installed a Yubikey as a secondary second-factor option and I carry the Yubikey with me just in case. Chrome pops out the Bitwarden DUO Redirect Connector page and then just sits there and spins. There’s nothing wrong or different on the DUO end as far as I can see; it’s only Bitwarden’s 2fa that’s causing problems with it.
EDIT: just tested Leostream, another app my company has that uses DUO for 2fa. It behaves normally and we get a DUO push prompt upon login to verify the user, same as we always do. I used the same Chrome browser on the same PC to connect to Leostream that I did for Bitwarden. Leostream can get an instant DUO push. Bitwarden hangs.