Verge thinks an element exactly off of the screen is in the viewport about verge HOT 1 CLOSED

Thanks @yuchant! It seems to be due to the scrollbar. CSS considers the scrollbar to be in the viewport. That explains why left: -300px is in the viewport but right: -300px isn't. It's weird that switching to position: absolute changes the result though, isn't it? To be safe you could add extra space like right: -320px or use verge.inViewport(drawer, -20) to be sure it's at least 20px in the viewport. Or workaround the issue by transitioning width rather than right like

.drawer {
  position: fixed;
  width: 300px;
  right: 0;
  top: 0;
  bottom: 0;
  transition: width .2s ease-in-out;
}

.drawer.is-offscreen {
  width: 0;
  overflow: hidden;
}

from verge.