I’m using Safari at home, and Explorer at work. Recently I’ve noticed weird things happening, though I’m not sure if it’s happening with both browsers. I suspect it might not be happening with Explorer, but I’m not sure. (Explorer might be weird in another way.) This morning I replied to a comment on Facebook. When I attempted to navigate away from the page, I got a warning that I had not posted the comment I’d just posted, and would I like to leave the page. I just commented on another post, and I saw that after I posted, my post was duplicated in a fresh Reply box. A couple of days ago, I put an item in my Amazon shopping cart. When I went to Amazon the next day, it said I’d put three of the item into my cart.
Is anyone else having this issue? Is there something wrong with the browser? Or might my keyboard be going funky and registering ‘enter’ more than once? Or could it be the Internet being slower than my fingers?
Can’t help you with Amazon, but I’ve encountered the same double post on FB using Firefox. At first I thought it was me, but your post here (using browsers I don’t use) leads me to believe the problem may lie with the websites, the “network” and changeover to TLS handshakes, or a combination of both.
Still happening to me on FB, using Safari.
I can’t address your Amazon issue either, but I have had the same thing happen on FB once in a while. You just have to wait it out. It’s probably high traffic on their servers. When you get that pop-up click on wait and it should post your comment shortly. Patience.
In he office today, so I have to use Windows and Explorer. The double-posts are happening on FB. (Yes, I am working! Just taking a break.) I did not notice the phenomenon on Amazon the past couple of days, in either browser. Might’ve been a one-off. Anyway, it looks like a Facebook thing, and not something wrong on my end.
Peanuthead: ‘Wait’? 
I’ve had it happen to me on Facebook, and I’ve had someone else complain about it in the last week on another forum. So there’s something that’s weird going on with something that’s happened recently.