Man, i am programmer with over 30 years experience. I do know there’s no MY code which sets this cookie. There’s just apache and resin, that’s all. Maybe apache module?
I did strings|grep for all modules but found nothing
edge, or edge chromium ? if edge it block a lot of thing and try to encapsulate for security reason, which make it less compliant to what other browser do.
if edge chromium, I would try chromium browser to see if it show the same pattern