How to remove/hide title bar in Windows 10?

Given that the answer provided in the linked question still had issues (didn't work in Vista - follow up suggestion reduced taskbar icons), I don't believe there's much hope for a suitable function within Win 10.

However, the comment provided by Mokubai suggesting to use Autohotkey may still be applicable here.

The following code in AHK will remove the Title Bar for the active window.

WinSet, Style, -0xC00000, A

mostly by pressing F11 will work for most of the stuff i guess ( for example it works with windows explorer, chrome, etc) and if not then try Alt + Enter, anyway there will be some stubborn software who no matter what you do won't allow us to hide the title bar. Enjoy

Note that this also corresponds to Tablet mode vs. Desktop mode (Windows 10). I've discovered that in Tablet mode, it auto-hides the title bar unless you put your mouse at the top.

As for me personally, I find this extremely obnoxious, even if I'm using the touch screen, so I put it in Desktop mode.

To switch, click the icon at the bottom right of Windows 10 (where you set e.g. brightness, airplane mode, network settings, etc.). By default, you may have Tablet mode as one of your primary options; if not, click on Expand. (https://dottech.org/174526/how-to-switch-between-tablet-and-desktop-mode-in-windows-10-tip/)

To switch the default mode when you log in, go to the Windows 10 Settings app, click System => Tablet mode. It's straightforward from there.