I've gotten scales automatically upon opening an egg or hatchling's page before but this is the first time I realised it can happen with an adult as well.

Had you previously nurtured those pets via their pet profile page before?

My only assumption is you're resubmitting the form, which is basically repeating the last nurture submission. If it happens to be after nurtures have reset and all other conditions are valid, it will re-process the nurture.

I don't think it necessarily should work this way so if this is the case, I'll have to take a look. But it's my best guess as to what's triggering it.

Possibly so for all the other times it's happened (when people post links in region chat for nurtures) but for the one I screenshotted, I don't know how that could be the explanation as I didn't refresh it. As far as I'm aware I'd never opened that page before, certainly not within the same session. I mean, the pet's older than my account age, so I definitely never nurtured it before. Usually when it resubmits the form it comes with a 'are you sure you want to resubmit this form?' and a 'this pet has already been nurtured today' error message.