MacOS – Full screen YouTube still shows Dock and Menu Bar

If you try to make a window bigger than the size left by the Dock, by dragging the bottom of a window yourself, you will notice that you can't do it. This is because the Dock already behaves like a Windows Taskbar: you can move windows behind it but not resize windows beyond it.

The problem lies with the tool that you are using to resize the window-it is extending the window more than it should do. Try using a different tool to do the resizing or resize the windows yourself.

You can use spotlight (⌘-Space) to do most anything. ⌘⇧A opens Apps folder, ⌘⇧H opens Home folder.

To fix your problem: Try opening the Terminal app (launch via Spotlight). Then type killall Dockand press return. That will attempt to kill the Dock process and relaunch it.

If that doesn't work you can check Activity Monitor (launch via Spotlight) and search for the Dock process to see if it's running at all, and if so, if it's hanging.