Javascript forces browser to render DOM documents

When the browser executes a section of JS code, the rendering DOM document is not updated immediately, but the DOM document is updated when the entire code is executed. The browser is implemented so as to maximize performance. But this implementation sometimes brings us some unintended negative effects. When JS accesses the following DOM properties, the browser renders the DOM document first, and then gets the associated properties. This forces the browser to render the DOM document immediately. OffsetTop, Offsetleft, offsetwidth, offsetheight
ScrollTop, ScrollLeft, ScrollWidth, scrollheight
ClientTop, ClientLeft, ClientWidth, clientheight

Javascript forces browser to render DOM documents