&gt; Threads won&#x27;t be able to share FBO&#x27;s or VBO&#x27;s, but we&#x27;re working on SharredArrayBuffer, which will allow multiple threads to share data (more like C style arrays than JS style lists, they still would have to be glBufferData&#x27;d to VRAM from RAM).<p>It would be amazing to have fast GPU-GPU transfer. Is it the case in Firefox that using texImage2D&#x2F;texSubImage2D on a main thread context with a worker &lt;canvas&gt; will result in a guaranteed GPU-GPU transfer? Or does that download the pixels to the CPU and re-upload them?<p>&gt; Isn&#x27;t that the case for all applications?<p>Yes, but I haven&#x27;t been following GPU tech recently so I wasn&#x27;t sure if that still applies universally. Maybe some day we&#x27;ll get preemptive multitasking on GPUs :)