Right now items in the user dropdown menu and items added to the main menu using mw.util.addPortletLink have an extra between the icon and the text in addition to the margin, this should be removed. The space was removed from the main menu in PHP as a part of T292452 with this change, but the change was never applied to mw.util.addPortletLink or the user menu.
In the main menu, you can see that the icons added by the skin in PHP don't have the extra space, but the "Foo" menu item that was added using mw.util.addPortletLink does.
In the user menu, all the menu item have the extra space.

