1. Use fetch API to make a request in an HTML page - see request at server (encountered with Node.js server)
2. Reload page - see request at server (again) but with a duplicate request as well
The expected behavior is that every time the page loads there should only be one request sent to the server, but in fact after the first request Safari will make duplicate requests each subsequent page load. That is, two requests will be made at a time.
The bug was first encountered June 22 2018 on a 2017 MacBook Pro
The bug does not occur in google Chrome.
See this Stack Overflow post for more details:
*** This bug has been marked as a duplicate of bug 199492 ***