: the <em>virtual screen</em> and the window <em>content area</em> or <em>content area</em>. Both use the same unit: <em>virtual screen coordinates</em>, or just <em>screen coordinates</em>, which don't necessarily correspond to pixels.</p>
<p><img src="spaces.svg" alt="" style="pointer-events: none;" width="90%" class="inline"/></p>
<p>Both the virtual screen and the content area coordinate systems have the X-axis pointing to the right and the Y-axis pointing down.</p>
<p>Window and monitor positions are s