Does your employer know? HR would probably have a fit if they found out it was publicly posted.
0: https://metro.co.uk/2018/11/09/can-your-boss-stop-you-talkin...
They are only capable of following policy and law - which, in my country (US) means it’s perfectly fine to discuss salary.
Note: “HR” (Human Resources) describes the resource pool in relation to the corporation, not a collection of “resources” available to a human. As a department, HR only ever exists to serve the corporation. Even if you walk into the dept to fix a pay stub (a legal concern) or get a mental health referral (it’s expensive to hire new emps after burning them out…)