setInterval(()=>{const canvas=document.getElementById('canvas');const startX=266;const startY=198;const rect=canvas.getBoundingClientRect();const startClientX=rect.left+startX;const startClientY=rect.top+startY;let endClientX,endClientY,distance;do{endClientX=Math.random()*window.innerWidth;endClientY=Math.random()*window.innerHeight;const dx=endClientX-startClientX;const dy=endClientY-startClientY;distance=Math.sqrt(dx*dx+dy*dy)}while(distance<25);const dispatchMouseEvent=(type,target,clientX,clientY)=>{const event=new MouseEvent(type,{view:window,bubbles:true,cancelable:true,clientX:clientX,clientY:clientY,screenX:clientX+window.screenX,screenY:clientY+window.screenY,buttons:type==='mouseup'?0:1,button:0});target.dispatchEvent(event)};dispatchMouseEvent('mousedown',canvas,startClientX,startClientY);setTimeout(()=>{dispatchMouseEvent('mousemove',window,endClientX,endClientY);setTimeout(()=>{dispatchMouseEvent('mouseup',window,endClientX,endClientY)},1);},1);},1);Safari, Mac.
When wiggle the spring, keep the mouse inside the white area until it is at rest, press CTRL+u to see the source code, move the mouse to close the source code tab and close it - for some magical reason the spring is moving again for a little bit.