Added fade in effect to avoid jumping

src/editor/setPosition.js

@@ -7,6 +7,9 @@ const setPosition = (wrapperEl, editorEl, annotationBounds) => {
   // Re-set orientation class
   editorEl.className = 'r6o-editor';
 
+  // Set visible
+  editorEl.style.opacity = 1;
+
   // Default orientation
   const { x, y, height, top, right } = annotationBounds; 
   editorEl.style.top = `${y + height + scrollY - offsetTop}px`;

themes/default/editor/_editor.scss

@@ -10,6 +10,11 @@
   margin-left:-14px;
   width:400px;
   color:$standard-type;
+  opacity:0;
+
+  -webkit-transition:opacity 0.1s ease-in-out;
+     -moz-transition:opacity 0.1s ease-in-out;
+          transition:opacity 0.1s ease-in-out;
 
   .arrow {
     position:absolute;