Qlik Sense: ErrorCode.16 in mashups

The mashup page shows an extra element with error code 16 in recent Qlik Sense versions.
This was not happening in older Qlik Sense versions (Versions before June 2017, such as 2.x, 3.x)

Sample code:

<script src="https://qlikserver1.domain.local/resources/assets/external/requirejs/require.js"></script>
<script type="text/javascript">

    //Read server connection
    var config = {
	host: "qlikserver1.domain.local",
	prefix: "/",
	port: 443,
	isSecure: true
	};

    //Start here.
    $(document).ready(function () {
        console.log("document ready -------------------");
        setupRequire()
    });

    function setupRequire() {

        require.config({
            baseUrl: ( config.isSecure ? "https://" : "http://" ) + config.host + (config.port ? ":" + config.port : "") + config.prefix + "resources"
	});

        require(["js/qlik"], function (qlik) {            

            try {
                qlik.getAppList(function(list){
                    console.log("received list");
                }, config);
            }
            catch(error) {
                console.error(error);
            }

        });   
    }

</script>

The app list is fetched correctly but the following error is shown directly in the HTML:

ErrorDialog.Title

ErrorCode.16
Common.Refresh



Environments:

• Qlik Sense June 2017 and later

In recent Qlik Sense versions, in order to limit the number of WebSockets opened, Qlik Sense will close the WebSocket connection immediately after getting the app list, which is getting interpreted as an error.


Solution:
Use app.global.getAppList(), which keeps the WebSocket open. app.global is intended to be used if there are several API calls that need to be done.

const global = qlik.getGlobal(...)
[...thousand of lines later....]
global.getAppList()

For the sample code mentioned above, it will look like this:

require(["js/qlik"], function (qlik) {            

            try {
                qlik.getGlobal(config).getAppList(function(list){
                    console.log(list);
                });
            }
            catch(error) {
                console.error(error);
            }

        });