How to debug why MS Edge/IE11 does not load sourcemap
<p>I made some source+map concatenation and result works in Firefox and Chrome, but does not even request bundle.js.map from webserver in MS Edge and IE11.</p>

<p>Actual JS file is served from <a href="http://localhost:8080/bundle.js">http://localhost:8080/bundle.js</a></p>

<p>bundle.js ends with line:</p>

<pre><code>//# sourceMappingURL=bundle.js.map
</code></pre>

<p>Tried both end it with new line and without, does not work in both cases. Is there some checklist to look at or even some "validator"?</p>