Linked Questions

Popular Questions

I have a toggle button true/false on my extensions popup.html page. The button has a 0.4 transition animation. Sometimes when opening popup page I could see the button sliding into its final position so I set default transition time in CSS to zero and used JS to change it back to 0.4 after popup.html loaded.

My init function reads the value from chrome storage and sets the button in proper position. After that it adds a new class to my checkbox which has transition time set to 0.4s. It works if I wrap my last step in setTimeout with 0ms but if I don't use setTimeout and leave the querySelector in same place the style gets applied so fast that I can once again see it happening while opening popup.html. My question is why is this happening? Shouldn't this same thing happen with setTimeout at zero as well?

function init(){['switchState'], function(result) {
    var switchState = result.switchState;
    document.querySelector("input[type='checkbox']").checked = switchState;
    setTimeout(() => {
    }, 0);

.slider:before {
   position: absolute;
   content: "";
   height: 25px;
   width: 25px;
   left: 2.5px;
   bottom: 2.5px;
   background-color: white;
   transition: 0s;
   border-radius: 25px;
.animated-slider:before {
   transition: 0.4s;

Related Questions