Why do I repeatedly, but not always, see box saying that I need Flash Player so click here?

Question

I use Facebook a lot. I watched a video earlier that someone had posted and all went well. So a little later, when I wanted to show it to my daughter, once again this darn box popped up which since I can't resolve it as my Windows 8.1 apparently comes stock with Flash Player so clicking for a new installation does NOTHING internally.
The Adobe site ran it's check and I saw that little floating cloud that verified that I have Flash Player installed and that it works and is Enabled. I've also researched this NUMEROUS times and found that it's easy to just click the gear in top-right on my IE-11 and Manage Add-Ons then make sure it is Enabled, which it always has been.

Answer 1

I'm back! Actually, this issue has been happening to me every now & then but I'd just given up on dealing with it. But now I'm motivated again.
I clicked on a video link in Facebook that sent me to NASCAR | Facebook which turns from the https URL to those two words on this site for some odd reason, and it just popped a box telling me saying Flash Player Upgrade Required - Get Flash Player and the video's image never displayed under that and it couldn't be played.
Then once again I went thru all of the steps to insure that both I do actually have Flash Player and that it is Enabled. I do and it is. I also read somewhere to click the gear icon in IE then click Safety > ActiveX Filtering. I do that and I see a checkmark next to ActiveX Filtering. I've tried it both with a checkmark and without one and there's no difference.
I have Windows 8.1 fully updated, IE-11 and Flash Player
I see the swinging tire swing image in #5. Verify if Flash Player is installed at Flash Player Help.