The Who Is / Was Online Status Icons shows all users who are online or who was online and when their last activity occurred.
This is only visible to Registered users and only if they are logged in.
You can turn this status off (become invisible) on the Who/Is Status Bar From your User Profile Control Panel.
This also hides your activity status if someone visits your profile page
WITH VISIBILTY TURNED ON:
WITH VISIBILITY TURNED OFF:
This Also Hides Your "Online Status" on Threads & Posts in the Posts Author Side Panel
WITH VISIBILTY ON:
VISIBILITY TURNED OFF
It also Shows Your Status as "offline" in the Signature Block
