tilemill-josm-remote/assets/josm-remote.css

Open a JOSM editing session covering the current map view.

.josm-remote a {
  width: 88px;
  z-index: 1;
  position: absolute;
  top: 65px;
  left: 10px;
}

.josm-remote a.disabled {
  pointer-events: none;
}