Fix missing characters caused by concurrent editing

www/pad/inner.js

@@ -694,6 +694,18 @@ define([
             the first such keypress will not be inserted into the P. */
         inner.addEventListener('keydown', cursor.brFix);
 
+        /*
+            CkEditor emits a change event when it detects new content in the editable area.
+            Our problem is that this event is sent asynchronously and late after a keystroke.
+            The result is that between the keystroke and the change event, chainpad may
+            receive remote changes and so it can wipe the newly inserted content (because
+            chainpad work synchronously), and the merged text is missing a few characters.
+            To fix this, we have to call `framework.localChange` sooner. We can't listen for
+            the "keypress" event because it is trigger before the character is inserted.
+            The solution is the "input" event, triggered by the browser as soon as the
+            character is inserted.
+        */
+        inner.addEventListener('input', framework.localChange);
         editor.on('change', framework.localChange);
 
         // export the typing tests to the window.