Out of desperation at stopping the broadcast, I scanned my Activity Monitor, and saw the site on the list. Yet, in flipping through every open window, the tab was nowhere to be found, so Safari somehow closed the tab, but kept the site open, as seen in the Activity Monitor!
And the more I'm using Safari (I hadn't used it for a couple months), the more glitches and flubs and bugs I'm experiencing, websites suddenly becoming a different one! Mouse clicks going unresponsive. Clicking the back arrow button, constantly showing me two options, instead of just going back to previous tab, as it's supposed to, and the same with hitting the new tab button, instead of just opening a new tab, it shows me a dropdown menu of all the currently open windows! And I still can't figure out how to see a list of all open tabs, as some browsers have in their own Task Manager, which lists all open windows & tabs....