In times of the WebKit bug/security issue I do believe, that it is a thing ;-)
www.macrumors.com
Just think about the bug a few weeks/months ago where all closed tabs (from several months ago) just came back...
Apple = the privacy company.... NOT!

Safari Bug Allows Websites to Track Your Recent Browsing Activity in Real Time [Updated]
A bug in WebKit's implementation of a JavaScript API called IndexedDB can reveal your recent browsing history and even your identity, according...

Just think about the bug a few weeks/months ago where all closed tabs (from several months ago) just came back...
Apple = the privacy company.... NOT!