Every time you press Ctrl + +Key window will be zoom 10% , also you can reverse it by ctrl + - key. If you want to zoom YouTube video only you can click on zoom box icons (Rectangular and square size icons) in a YouTube video at the bottom right hand side.How do you zoom in home?
In order to zoom in, you just press control (Windows) or command (Mac) and the + key. (Technically you're pressing the = key because you'd need to press shift to make a plus, but thinking of it as the + key makes more sense since it's zooming you in.) To zoom out, press control/command -, and press control/command 0 to set things back to normal.