&gt; How similar&#x2F;different is the OffscreenCanvas proposed spec from the CanvasProxy proposed spec? I thought there were going to be synchronization nightmares to CanvasProxy and that is why browser vendors avoided implementing it.<p>I don&#x27;t know enough about our graphics stack, or the CanvasProxy spec to answer that.  I just try to show why people should be excited about the hard work done by Mozilla employees, contributors, and volunteers.<p>Also, specs are not laws until they&#x27;re candidate recommendations, and a lot will never be implemented.  I should do a &quot;how a bill becomes a law&quot; post about web standards bodies...<p>&gt; Is the DOM canvas neutered after calling transferControlToOffscreen? Meaning, can you get a context and draw to the canvas concurrent with the Web Worker, or is the DOM Canvas inaccessible after control is transferred?<p>Open your dev tools and find out.  Fewer chars than your question typed out:<p>a = document.createElement(&#x27;canvas&#x27;), a.transferControlToOffscreen(), a.getContext(&#x27;webgl&#x27;)<p>&#x2F;&#x2F; null<p>&gt;  Thanks AGAIN, Mozilla!!<p>We&#x27;ve got your back, son.