in short, no, "Autoclick" is not a feature of windows 10.
however, I cannot recall that being a feature in previous versions of windows, are you sure it's not a third party program (there are a few around)?
I have just had a look in Windows 7 and the nearest I can find to what you describe is "activate a window by hovering over it with the mouse" but that will not perform a left click on a button when the mouse stops. this feature IS still available in windows 10 , through control panel -> ease of access -> make the mouse easier to use.
can you give us more information about how it works and perhaps a screen shot of the settings page or where you are currently able to activate the feature.