Wisej always uses HTTP for data stores requests: datagridview, listview, fullcalendar, and possibly others. Data requests are done using a data store class that caches the pages and requests the visible range of data. Always uses http because: 1) http is deflated at the browser OS level, 2) with http the request is matched with the response, 3) its easier to debug in chrome. The most important reasons are 1 and 2.
Also images and postback handlers (like the canvas control) are handled through http requests. For example, the websocket push part tells the canvas control that it needs a new set of canvas instructions, the control fires an ajax request to get the list of instructions and it gets a response with the data.
And the initial load is naturally done using http since you need http to upgrade to websocket and we use the initial request to return config data to the client.