Ok, that was easy. Comparing to method mentioned by HRK in another recent thread. This is using Windows 10. With video playing, right click to bring up options. Select (left click) this: < > Copy imbed code
If you haven't already, open a SF new message window, select the video option second from right at the top. It brings up this: [FLASH_VIDEO] [/FLASH_VIDEO]. Left click in between to place cursor there, and left click "Paste" icon from "Edit" row of dropdown options you find by clicking the three little lines upper right in SF message window. Voila. It's here. Hit "Post Now" on lower right. You've done it. Note: this is for tech dummies like me who need to be told almost everything sometimes.