I just tried to give the Linux preview a shot. Unfortunately, I found that after the web sign-in thingy, where it then asks for my master password in the native application, a generic "Cannot sign in" error message would immediately appear.
Next I tried entering an intentionally wrong master password and found that a spinner would appear and it took a second or two to return an error. I narrowed it down to the doublequote (") character in my password. After changing my master password to no longer contain a ", the sign-in worked normally.
Expected behavior is that any character works as master password.
1Password Version: 0.8.4 @0e67d21
Extension Version: Not Provided
OS Version: Not Provided
Sync Type: Not Provided