Sorry about that. This add-on detects if they are mining without your consent and salon.com asks you at least once. When you accept this, if you click in the icon, it detects that it's mining. Sometimes, webpages delete the mining code to hide it when you accept and the add-on doesn't detect it.
If you need to make sure that a site is mining or not, you can use our webpage (https://notmining.org/) to check a webpage. If we don't detect with our webpage, you can report this page and help us to improve this tool sending an email to email@example.com