Identity Safe passwords don't show for new and edited logins

I have an Identity Safe problem that has only occurred since I upgraded my computer a few months ago.

I can log into Identity Safe successfully.  The problem occurs when I create a new login (for example, for a bank account).  The password field does not show any characters at all as I type, not even the usual dots.  Despite this, if I save the new login, the saved password can still be viewed in the list of logins.

A similar problem happens when I edit an existing login.  I've attached a screen print.  Even though there is a password, the password field appears as a blank white space (surrounded by a red, amber or green border, depending on how secure the password is).  However, if I click the apparently empty space, the cursor goes to wherever the end of the password is.  I still can't see any characters, but if I highlight where they should be, then copy and paste into Word, the password will appear correctly (in Word).

My computer is a Dell XPS13 Touch with HD screen.  I use Windows 10, with the recent updates.  I've just checked Norton's website and I have the latest version of Norton 360.  My problem is with the Identity Safe stored on my computer, not the online version.

Does anyone know if there is a fix for this problem?