Avoid duplicate events firing on creation

Some cleanup of the editor hide/show entanglement with creation events
is very desperately needed.

Closes #761

h/js/host.coffee

@@ -426,7 +426,45 @@ class Annotator.Host extends Annotator
       method: 'addToken'
       params: token
 
-  #Save the event for restarting edit
   onAdderClick: (event) =>
+    """
+    Differs from upstream in a few ways:
+    - Don't fire annotationCreated events: that's the job of the sidebar
+    - Save the event for retriggering if login interrupts the flow
+    """
+    event?.preventDefault()
+
+    # Save the event for restarting edit
     @event = event
-    super
+
+    # Hide the adder
+    @adder.hide()
+    position = @adder.position()
+
+    # Show a temporary highlight so the user can see what they selected
+    # Also extract the quotation and serialize the ranges
+    annotation = this.setupAnnotation(this.createAnnotation())
+    $(annotation.highlights).addClass('annotator-hl-temporary')
+
+    # Subscribe to the editor events
+
+    # Make the highlights permanent if the annotation is saved
+    save = =>
+      do cleanup
+      $(annotation.highlights).removeClass('annotator-hl-temporary')
+
+    # Remove the highlights if the edit is cancelled
+    cancel = =>
+      do cleanup
+      this.deleteAnnotation(annotation)
+
+    # Don't leak handlers at the end
+    cleanup = =>
+      this.unsubscribe('annotationEditorHidden', cancel)
+      this.unsubscribe('annotationEditorSubmit', save)
+
+    this.subscribe('annotationEditorHidden', cancel)
+    this.subscribe('annotationEditorSubmit', save)
+
+    # Display the editor.
+    this.showEditor(annotation, position)