I have an out-of-the-box instance of ArcGIS Web AppBuilder developer edition - the startup.bat file is unmodified and includes the lines:
REM open the url <SPAN class="keyword token">in</SPAN> browser
START http<SPAN class="punctuation token">:</SPAN><SPAN class="operator token">/</SPAN><SPAN class="operator token">/</SPAN><SPAN class="operator token">%</SPAN>FQDN<SPAN class="operator token">%</SPAN><SPAN class="punctuation token">:</SPAN><SPAN class="operator token">%</SPAN>port<SPAN class="operator token">%</SPAN><SPAN class="operator token">/</SPAN><SPAN class="operator token">%</SPAN>wabVirtualPath<SPAN class="operator token">%</SPAN>
EXIT <SPAN class="number token">0</SPAN><SPAN class="line-numbers-rows"><SPAN></SPAN><SPAN></SPAN><SPAN></SPAN></SPAN>
However, when I start a new session on my PC, it runs as https://localhost:3344/webappbuilder - even if I forcibly change the URL to http:// it immediately reverts to https://
This is causing a problem when I try to access ArcGIS Server REST endpoints which are not served via https.
For example, when trying to add a sample layer via the Local Layer Widget I get an error message about insecure content:

I'm working in a corporate environment and don't have the option of serving my local layers via HTTPS, so I'd like to know whether it's possible to force Web AppBuilder to run on HTTP.