After you have created new certificate with command "certAdd" it will shown as currently selected (see screenshot). But in reality you can't use it for posting until you click on it. So it is not actually selected. Only when you click on this cert, certificate register name will be added to users.json in section with sites (as "cert" property).

You can trace this bug on nanasi board, for example.
I think that label "currently selected" must be displayed only when name of certificate issuer added to sites section in users.json.
@HelloZeroNet is this yet a issue?
Thanks it was fixed some months ago: https://github.com/HelloZeroNet/ZeroNet/commit/dafe9981a241e5ff170bd989abcd77e85acaf3aa
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Thanks it was fixed some months ago: https://github.com/HelloZeroNet/ZeroNet/commit/dafe9981a241e5ff170bd989abcd77e85acaf3aa