Delete the contents of the W10 profile folder, and copy in the contents of the Mac profile folder. Then, delete the pkcs11.txt file in the W10 profile folder. To open the profile folder from TB, Help/Troubleshooting, Profile Folder, Show in Finder (Mac) or Open Folder (W10). Close TB while copying or pasting profile files.

You said "delete the content of the W10 profile folder" and then "delete the pkcs11.txt file in the W10 profile". The pkcs11.txt file is inside a folder in Profile folder.

Shouldn't this procedure be documented somewhere?

Also, strange enough: I see 2 folders in W10 (which is the TARGET not the SOURCE) profile folder (brand new installation)

Yes, that procedure should be included in the support article, if someone volunteers to do it.

There might be multiple profile folders, depending on how TB was installed or upgraded. Help/Troubleshooting, about:profiles, shows which profile is the Default.

thanks, would you mind fixing the inconsistency in the procedure in your first step? It would be helpful to me and for the future users.

I don't see any inconsistency. When you copy in the contents of the Mac profile folder into the W10 profile folder (or vice versa), there will be a pkcs11.txt file. Delete the file before restarting TB.

I see, thanks.