When you send a follow request, the button stays active (for example, when you log in to Pleroma the login button will be disabled, this isn't the case here). This even allows you to send multiple follow requests[1]
When I send a follow request to someone with a locked account and I refresh the page I don't see that the request has already been send. I also can't seem to cancel the request from the pleroma-fe.
When I try this in the mastodon-fe I do get visual conformation: I click 'follow', the icon changes to an hourglass which allows me to cancel the request, if the request is accepted the icon changes again.
I think the pleroma-fe button should have similar behaviour.