Hello again @BiggyD!
in the "Organize with favorites and tags" it does say: "To apply a tag to additional items, drag the items to a tag in the sidebar." Dragging and dropping seems much faster and easier.
The guide I provided includes two different sections, 1) Organize items on 1Password.com, and 2) Organize items in the apps.
Dragging an item to the tag in the sidebar applies only to the desktop app and not to items being managed/tagged through 1Password.com.
BTW, what is 1Password 8 desktop? I have windows 10.
1password is available for use in a few different places. 1Password.com, the apps (desktop/mobile) and browser extensions. 1Password 8 for Windows is our desktop application for the Windows platform. If you'd like to download this and give it try, you find it on our downloads page here.
I hope this helps, but we'll be here if you need further assistance. Have a great day!