Prevent flash of multi-level fields when form editor loads

[kevinwhoffman]

Issue Overview

Every time the form editor loads, the multi-level fields appear on screen for a half second before they are hidden by JS.

Expected Behavior

The page should load with only default fields visible.

Current Behavior

The page loads with all fields visible before JS hides some of them. Any field that is visible here but not in the screenshot above should be hidden by default.

Possible Solution

WordPress includes a js body class on admin pages when JavaScript is enabled. We can use that selector to hide fields by default via CSS rather than waiting until JS processes the DOM and then hides them. This means the page loads with the correct styles by default without having to wait for JS to parse the DOM. For example:

.js _give_display_style_field { display: none; }

Steps to Reproduce (for bugs)

Load the form editor screen and watch as the multi-level fields appear briefly before being hidden.