How can I trust a computer browser I untrusted for iCloud.com? I clicked "Do not trust" when signing into iCloud in Safari in my Mac.  How can I trust the browser now? so I won't be prompted for the two-factor code any more.

Note: I guess If I click "Sign out of all browsers" would offer me to trust again, but that would reset this setting on other browsers too, which is not what I want.  

Any help much welcome.
If you open a private browsing browser, you can determine if local storage or a cookie is responsible for this trust.

That's much easier than the sign out everywhere, and that might not invalidate the trust cookie as well as the auth cookie if they are distinct entities.