XWIKI-21029: StaticListClassFieldIT#itemsEditor is flickering

xwiki-platform-core/xwiki-platform-appwithinminutes/xwiki-platform-appwithinminutes-test/xwiki-platform-appwithinminutes-test-pageobjects/src/main/java/org/xwiki/appwithinminutes/test/po/StaticListItemsEditor.java

@@ -141,7 +141,9 @@ public void moveBefore(String valueToMove, String beforeValue)
 
         // We move the item from the center, so we need to ensure that we actually move it with an offset of half its
         // width to be sure it's before the other item element.
-        int offsetX = - (itemToMove.getSize().getWidth() / 2);
+        // Adding a few pixels more (10) to make sure to pass the threshold where the passed element is moved to 
+        // the next position in the list.
+        int offsetX = -(itemToMove.getSize().getWidth() / 2) - 10;
         int offsetY = 2;
         getDriver().moveToTopLeftCornerOfTargetWithOffset(itemBefore, offsetX, offsetY, actions).release().perform();
     }