Position the edit popover pointer in the center of the edit block.

Author: g1eb

dist/datetime-input.css

@@ -92,7 +92,7 @@
   width: 1em;
   height: 1em;
   top: -0.55em;
-  left: 47.5%;
+  left: 47.8%;
   z-index: 2;
   border-color: #aaa;
   border-style: solid;