I often post adds with lot of pictures in several different sites. But when click on "add picture" Firefox always opens window for picture upload in upper left corner of browser. Try to position it in the center or any other position is of no avail, because window keep opening in upper left corner of Firefox browser. Every time i have to upload a picture, I must drag File Upload window from upper left corner to the center. Since I have a big 43" pc screen this is very annoying. I have to every time reposition it to the center of Firefox browser window. Why Firefox or Win 10 do not remember last File Upload window position but keeps opening it in upper left corner ?